When sending SMS messages in BIG SMS, remember that a standard SMS message is limited to 160 characters. This limit can be reduced when you use emoji or special characters. If your message is longer, it is automatically split into several SMS messages. Depending on the mobile network and the recipient’s phone, these parts may be shown as separate messages or joined back together.
Why long SMS messages can split
If your long SMS messages are being delivered as separate short messages, you can try this compatibility fix.
Enable the compatibility fix
Go to the BIG Launcher home screen, tap the three dots next to the clock, and choose “Preferences”. Then choose “Messages”. On the next screen, find “Compatibility fixes” and enable “Dual SIM card support”.
Send a long SMS again
Return to the SMS editor and try sending a long SMS again. After tapping “Send”, Android may show a dialog asking which SIM card should be used. If your phone has only one SIM card, simply confirm that option.
When this fix can help
In this case, enabling Dual SIM card support can help the long SMS arrive as one joined message instead of several separate short messages.