Asus Zenfone Max Pro M2 Baseband Unknown problem solved through this method.
Fix for Asus X01AD Max Pro M2 Baseband Unknown IMEI Null
Allow USB Debugging
The Diag Port will be activated automatically.
If there is no diag port, flash this firmware.
Then, in QPST Software Download, select Restore 1st. Examine the Phone’s COM Port (Diag Port)
Second, look through Asus Max M2.xqcn.
Click Start and wait for it to finish.
Restart the Phone Manually After Successful Restore
Congratulations, your baseband, and IMEI have been restored without the need for rooting or unlocking the BL.
If the IMEI is different, enter it
Using= Qwrite Writer CKT