ironpony wrote:
The phone is a Huawei P30 lite, it says, with the model being MAR-LX3A.
According to its manual, it should be compatible with 2G, 3G, and 4G networks. It's very likely that there is at least one of these in your area.
Potential solutions (in no particular order):
1) Restart messaging app.
2) Clear messaging history.
3) Move SIM card to a different phone and see if the problem follows the SIM card.
4) Clear messaging app cache.
5) Update the messaging app.
6) Backup and reset the Network settings.
7) Clear the system cache.
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Put the phone in safe mode and see if you can send a message.
9) Factory-reset the phone.
10) Check with your network provider to see if anything is screwy with your account.