Check your network settings first. Go to Settings > Mobile Network and toggle Airplane mode on and off to reset the connection. If the issue persists, remove and reinsert your SIM card. Make sure your APN settings are correct: APN should be ''orange.fr'', leave username and password blank. Update your phone''s carrier settings by checking for system updates. In areas with weak coverage, switch from 4G to 3G manually to maintain a stable connection.
Verify that your message center number is configured correctly. Go to Messages > Settings > Advanced > Message Center and enter ''+33695000695'' for Sosh. Restart your phone after making this change. Check if you have sufficient credit or if your plan includes SMS. Try sending a message to a different number to rule out recipient-specific issues.
Force close the app completely and clear its cache through your phone''s app settings. Uninstall and reinstall the latest version from your app store. Ensure your operating system is up to date, as outdated OS versions can cause compatibility problems. Free up storage space on your device if it''s running low, as this often causes app instability.