Mariner clone with stuck battery

#1
I've got a Voltbike Mariner clone (Rawbike) in Europe with a stuck battery. When I got home today I put it in unlock and pulled to remove, but the battery did not come off. Afterwards I could see the little round metal notch toward the top of the battery moving back and forth when I turn the key clockwise, but the battery seemed to have partially shifted so it couldn't get back into full "lock" state as it hits the plastic case. It looked like there's just a coupe of mm there that are off.

After trying to wiggle the battery and nudge it I managed to get it to successfully get back into lock state and the bike gets power. However the battery position seems unreliable in that if I try unlocking and sliding the battery out again it still doesn't come out and sometimes again goes into the lodged state, stuck in unlock until I semi aggressively jiggle it to be able to get to the off position again.

Has anyone seen this, or has any ideas for why the battery seems to be stuck this way? I was wondering if there was anything I could look into or try at home before going back to the store to figure it out.

Thanks