The 919 is a apart double confirm with seller already ...

The seller reply my question and state it’s a original import set

Maybe telco issue? At one occasion my telco had no network for 5 hours from Umobile. Always on Emergency Call, when got network, tried making calls and it cuts to Emergency Call.

is it the first few messages you typed/received on your RN5 or transferred from different phone?

group messages? or single contact message?

care to provide a bit more info?

done. good thing is they bring back battery % next to icon... bigger like old times 

I'm on my original battery. So far so good. SOT is lower than it used to, of course. But not bad af an old phone with original battery. I think it is obvious that your new battery is not a genuine one.

my wife still using RN5, and i also still using RN6pro.
still on original battery, check from the accubattery, battery health now around 75% capacify full charge. so as expected since 3years already.

yea, could be the new MIUI , might using more battery than original version that it come with.
another things, is ur apps. some apps might wake up the cpu more often than before. compare with the time when u just bought the phone.
OR ur new replaced battery is not genuine.

how much cost to replace it? i also thinking to do the change.

Its accuracy gets better the longer you use it because it keeps track of charging/discharging and estimates real battery capacity. If your battery life is short then it makes sense that its at 50% health.