Hi potomoc. I could be wrong, but in my experience once it tears, there is no real way to `repair`it as such...the only suggestion I could offer would be to use a strip of strong tape to hold it...a bit like a plaster. Leave the backing bit on it ...is it right to the edge of the perimeter? I assume it is.... I used to wear all -polyurethane systems....the newer `skin`systems I guess, are more or less the same. Is your system new ? Exposure to the acid in sweat over time usually causes that issue but would be unusual in a new-ish one. Mine never tore as such, but would get little `pin-holes` which would eventually get bigger.A strip of tape will help keep it stay the size it is....... Paul.