iPhone 5s wont always charge

Sorry for my bad english.

I took my phone to a bad repair service to change the battery, and since then, my phone only charges after few trys of plugging it and unplugging it.

I tried different cables and wall adapters but I always face the same problem.

When plugged to a computer it shows up and stay connected ( I think the charging port is not defected ) and it electrocutes me when I touch it. (only when plugged into a pc) .

I tried a DFU restore but that didnt help.

Thanks.