Hi @indianarox ,
if it is possible, switch off the device connected to the plugpack that is in the power strip and then remove the plugpack from the power strip and plug your tablet back into the USB ports and check if the problem is still there.
This is to isolate where the problem may be emanating from, the plugpack or perhaps the power strip’s ''built in adapter'' that is converting the AC power from the strip down to 5VDC that is necessary at the USB ports.