My charge indicator is showing it’s charging, but numbers not changing

I just changed the battery in my IPhone 5s. About a day later, my battery was showing 40%. Put it on the charging. It goes green, lightning symbol shows up. Checked it in about an hour, has not changed, but still showing green.

I have tried turning it on/off, done a full reboot, changed to two different charger plug ins, three different wires, still nothing. I’ve even have used it constantly, and the indicator still won’t change.

Does this sound like the phone is still charging, but something wrong with the battery indicator? It doesn’t even show anything when I go into settings under battery. Anyone got any ideas?

Also am wondering if anyone knows if I can take the SIM card out of this phone, and put it into another? I have the Straight Talk 5S. I understand as long as it’s an AT&T or t-mobile that uses a SIM card, I should be able to do it…