My iPad Pro (first generation) shuts down when plugged out

Ever since I installed the latest update last week, my iPad Pro shuts down as soon as it has been plugged out of the charger after a full recharge. I then have to plug it in again for it to restart, as it gives me the 'battery low' symbol, even though it's 100% charged. It was working again each time after I would do a hard reset, but this solution has stopped working (and it would shut down again anyway after being recharged fully again at the end of the day).

This issue also happened to me a few months ago after the previous iOS update, however the issue only lasted a few days and worked with the hard reset so I then forgot about it.

Any help at all would be really appreciated. Thanks!