Possible Ground Connection?
 

My Mini has been intermittently losing electrical power after parking. As in, absolutely no lights, no response to remote or anything at all. However, when I access the battery and release the negative battery cable, then reattach, power to systems is restored. I have tried a new battery, but symptom returned after 4 drives. I am not sure how to proceed, but I am afraid of getting stranded or doing severe damage.
Has anyone run into this, or having any suggestions?
Thank you so much for your time!

A possible ground connection issue often arises when electrical components behave intermittently, such as flickering lights, unstable signals, or devices failing to power on consistently. This usually happens when the ground wire is loose, corroded, improperly sized, or not securely bonded to the chassis or earth point.