[leodaves]

When both SIM card is inserted, only SIM 2 will work and SIM 1 won't work but if I remove SIM 2, SIM 1 will work. Either works, but both doesn't.

[xerxes]

When both SIM card is inserted, only SIM 2 will work and SIM 1 won't work but if I remove SIM 2, SIM 1 will work. Either works, but both doesn't.

How did the problem start?
Check if the phone has a valid baseband and IMEI?
Goto settings>about>baseband for baseband version
Dial *#06# for IMEI

Sent from my M5 mini using Hovatek Mobile

[hovatek]

When both SIM card is inserted, only SIM 2 will work and SIM 1 won't work but if I remove SIM 2, SIM 1 will work. Either works, but both doesn't.

What about when both SIMs are set to 2G only?

[EMMANUS]

Have you also checked if your phone has option for sim selection?
Either one sim or dual sim (standby).