WhatsApp number won't connect? What to check when the code doesn't arrive or Facebook's window won't load

If a number will not connect to the WhatsApp Business API, the cause is usually one of five things: the type of number (a landline or VoIP number often needs a voice call, not an SMS), a call menu or forwarding that swallows the code, a number that is still in use on WhatsApp, a blocked Facebook sign-in window, or a number limit on your plan. Work through them in this order. Each takes a minute to check.

SendFromChat is an independent product and is not affiliated with Meta or WhatsApp. It runs on Meta's official WhatsApp Cloud API. Meta's rules change, so where this page relies on Meta it says which page and when we read it.

Quick map: what you see and where to look

What you see	Look at
No SMS code arrives	1. Number type, then 2. voice code and call menus
A call comes but nobody can read the code	2. Call menus and forwarding
Meta says the number is already in use	3. Number still on WhatsApp
"Facebook didn't load" or an empty window	4. Blocked sign-in script
"You closed the Facebook window before finishing"	4. Start again; nothing was connected
A message about your number limit	5. Trial and plan numbers

1. Check the type of number

Meta's developer page "Business phone numbers" rates number types for receiving the verification code (read 30 Oct 2026; the page shows no date, and we read it as a text extract, not in a browser). It lists Mobile as recommended. For fixed line, freephone, premium rate, VoIP and some other types it marks SMS codes "Not Recommended", while voice codes are "Standard". For personal numbers and M2M/IoT numbers both methods are marked "Not Recommended", and pagers are not supported.

So if you are connecting an office landline or a virtual number and no SMS arrives, that fits what Meta's page says, and it is not necessarily a fault on your side. Ask for the voice call instead of the SMS. This does not mean a voice code will work for every landline or VoIP number; Meta marks it "Standard", and we have not tested every carrier.

The same page says eligible numbers must be owned by you, have a country and area code (short codes are not supported), be able to receive voice calls or SMS, and have scaled capabilities. If you are not sure the number meets all four, read WhatsApp Business API requirements first.

2. Voice codes, call menus and forwarding

A voice code is a call that reads the code out. It only helps if a person (or you) answers it.

• Meta's page tells fixed-line numbers to disable call forwarding or IVR features. It also says "A WhatsApp registration call cannot navigate an IVR." (read 30 Oct 2026).
• If your number sits behind a phone menu ("press 1 for sales"), the call never reaches a person. Route it to a direct line for the few minutes you need it. Meta's page says numbers behind an IVR can still be registered if they accept international calls and can route the code to a person.
• Check the number can receive international calls.
• Request the code when you can answer the phone. Do not start it and then walk away.

We do not know how many code requests Meta allows or how long it makes you wait between them; the page does not say. If you keep asking and nothing comes, stop and re-check the number type before asking again.

3. The number is still in use on WhatsApp

Meta's page says: "Numbers already in use with WhatsApp cannot be registered unless they are deleted first." (read 30 Oct 2026). If WhatsApp or WhatsApp Business is on that number today, you have a choice: use a different number for the API, which is the simplest, or delete the WhatsApp account on the number. Deleting means you stop using it in the app, so export anything you want to keep first.

The page also says a number that has been banned must be unbanned through Meta's appeal process before it can be registered.

For the full picture, including what Meta says about keeping the app alongside the API, read WhatsApp Business app vs API. SendFromChat's connection flow does not include a coexistence option today, so plan on a new number or on moving the number off the app.

4. Facebook's window won't load, or you closed it

SendFromChat connects a number with Continue with Facebook, which opens Facebook's own window. Nothing is connected until you finish it.

• The button says "Facebook didn't load". The dashboard then shows a note that an ad blocker or privacy setting (Brave shields, uBlock, Firefox strict tracking protection) is usually the cause. Allow connect.facebook.net for the site, or open the page in Chrome or Edge, then reload. This note is in our connect page's code (checked 30 Oct 2026).
• "You closed the Facebook window before finishing." Nothing was connected. Click the button again. Our connect page shows this message when the window is cancelled.
• "Facebook reported an error". Our page shows Facebook's own error text. Read it; it may say which step failed. If it points at the number, go back to sections 1 to 3.

5. Your number limit

When the number limit is reached, our connect page stops with a message that names the number using the slot and the limit for your trial or plan. Remove that number on the Connect WhatsApp page (its conversations stay) and connect again, or pick a plan. The limits for each plan are in plans, trial and limits.

After the number connects

The connected number shows Ready to send?, Meta's own check of whether it can send. Per our getting started docs, it lists what is in the way with a link to fix it, most often a missing card on the WhatsApp account (templates) or an unverified business (which only caps how many people you can message a day). Then you can run it from Claude or ChatGPT, the dashboard or the REST API; see how to send WhatsApp from Claude or ChatGPT.

If you want to try it, the 30-day free trial needs no card. Prefer to run Meta's API yourself? The Cloud API setup guide covers Meta's side. For country notes see WhatsApp Business API in Europe.

Sources

• Meta for Developers, "Business phone numbers" (no date shown): number types, voice and SMS labels, IVR, already-in-use and banned numbers. Read 30 Oct 2026 as a text extract, not in a browser.
• SendFromChat connect page code (FacebookConnect.tsx) and getting started docs, checked 30 Oct 2026: the messages described above, the "Ready to send?" check.
• Not checked: whether your carrier delivers SMS or voice codes to your number, and Meta's limits on code requests.

This is not legal advice. SendFromChat stores data in Mumbai, India; transfers from the EU and UK are covered by the Standard Contractual Clauses and the UK Addendum in our Data Processing Agreement.