Problem after charging connector repair

Hi,

I decided to try to fix the SteelSeries Arctis 7 (2019 Edition) wireless headphones.

The microUSB charging connector was broken and I couldn't charge the headphones.

The connector broke off from the PCB and caused some damage there. I gave up on soldering a new connector in advance, I decided to just use two wires for charging only.

When I opened the headphones, I immediately put a new battery in them - Maybe I didn't do that smartly because I did two things at once.

I soldered the wires where the connector was and applied hot glue around it so the wires wouldn't break right away.

First day - headphones looked fine. New battery seemed to be charging (LED gradually changed color from yellow to green).

test a few hours of operation - no problems.

The next day - the headphones won't turn on.

They only turn on when they are connected to the charger. When I disconnect them from the charger, they turn off after a few seconds and won't turn on. I tried the HW reset button.

I don't know if it's a problem with the new battery or a repair on the connector. It seems strange to me that they worked on the first day.
My main question:

The first day when I was soldering the wires for charging, I momentarily mixed up the polarity of +5V.

So I connected the charger with the polarity reversed, but after I realized it and put it in correctly, the headphones worked and I did the test for a few hours from battery.

Do you think the damage caused by reversed polarity would only become apparent the next day?

Do you have any tips on what I can try, let's say in amateur conditions?

Currently, the battery voltage is 4.1 V. They won't turn on unless I plug them into the charger. Then I can turn them on.

When they are connected to the charger, I can turn them on and pair them with the PC and they work - but they are not "wireless" then.

Thank you for any response, I hope you are doing well and have a lot of success with your work on YouTube.

Adam