Tablet only charges AFTER turning on

Samsung Tab A 10.1. Battery went dead. Plugged in overnight and would only charge to 5% and when plugged into an AMP reader, it reads less than 1 amp then drops to 0.

Turned device on and plugged in again. Charges perfectly, AMP reader shows 1.28 and doesn’t drop. Turned device back off and still is charging like normal.

Why might it do that? Is there a way to fix it or just have to use as is?