I have the sony xperia m5 E5663 in myanmar.Sim slot 1 cannot sense any sim sometimes.It said me no sim card no service although I put the 3g sim card and 2g sim card in each slot.It also shut dowm automatically often. How can I fix it.
Mine also have the same issue, suddenly shut down and I have to connect the charger in order to turn it on, lagging and heating problem. But after I done the hard reset method, it works..!! Been using it for 3 weeks after the hard reset and so far no problem. Just follow the steps in the link.
# third method - Install PC companion (Sony) then reinstall the firmware.