Chosen Solution
So as soon as my phone is plugged in it displays the charging animation however when I disconnect the charger the screen goes blank immediately without showing the battery low animation. Intermittently it comes on but is stuck in a bootloop.
I have found that bootlooping issues that occur only when plugged in may be caused by a battery issue (disconnected or connection issue). Has the battery ever been replaced before? For example, I had a phone (iPhone Xs) with a previous battery replacement brought to me for a similar complaint after the customer had dropped it. When plugged in, the phone would either display the charging symbol, or would bootloop. In this case, a battery replacement solved this issue.
Try cleaning out the charging port and if that doesn’t fix it replace the charging port
