A common cause is a poor internet connection; ensuring a stable Wi-Fi or mobile data connection is essential for message transmission.
Additionally, using an outdated version of the Messenger app may lead to such problems; regularly updating the app can help prevent these issues.
Another potential reason is that the recipient has unfriended or blocked you on Facebook, which would prevent your messages from being delivered.
To check, try searching for their profile; if it's inaccessible, this might be the case. Technical glitches within the app can also hinder message sending; restarting the app or your device might resolve these temporary issues.
If these steps don't resolve the problem, consider reaching out to Facebook Support for assistance.
You can access the Help Center through the Messenger app by navigating to Settings > Help > Report a Problem.
Alternatively, visit the Facebook Help Center online at https://www.facebook.com/help/messenger-app/desktop/ for further guidance.
If you’ve faced a similar issue, don’t hesitate to share your story here. You can also file a complaint on Xolvie to help others in the same situation.