It did it to me last night, too. I resolved it by going through the process of creating a new cloud project in Tuya IoT and then adding a new Tuya integration into HA with the new details, then disabling the original one. Devices have all come back with the same names, thankfully, so no need to change any automations.
It’s prompted me to look at LocalTuya, but that’s an even bigger nightmare, it seems.