We are sorry to hear that you’ve run into quite a tough situation with your Samsung Galaxy S6 Edge Plus after the battery change. Since you mentioned that the terminal came off the old battery and you didn’t notice, it’s essential to check all the connections again:
Ensure the new battery is properly connected to the motherboard. Sometimes, a loose connection can cause booting problems.
Inspect for any signs of physical damage on the motherboard, especially around the battery terminals or power connectors. Look for any visible burnt areas or broken traces.
If you're still unable to get past the boot loop or the phone is still giving you errors, would suggest taking it to an authorized Samsung repair center to fix the issue.
