Network wont return to 4g after drop to 3g

This problem happen to me several times. Drop from 4g to 3g (like making call), and it stuck on 3g. Usually i solve this by switching the network mode to 2g/3g and back to 2g/3g/4g to get back to 4g. Airplane mode not solve this. But the much worse is sometimes I cant even change the network mode. It says I am able to set on 3g or above for 1 sim card only. And i only use 1 sim card on slot 1. Please refer my screenshot.
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Ok, weird... you can start with going to your system settings -> system -> restore options -> reset bt, mobile and network
If that doesn't work then we need to log your phone in order to find out why