Make num pad write "," instead of "."

Hello

I have bought a num pad for my android device and often use excel.

My problem is that I want my numpad to write "," when I press the dot on it. Instead it writes ".". I have tried to change language to sort it out, but that doesnt help.

The numpad is this one: https://www.google.com/search?q=microsoft+numpad+on+android&prmd=sivn&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj6prWkgcP2AhU-AxAIHRU2AbgQ_AUoAnoECAIQAg&biw=1692&bih=1056&dpr=1.75#imgrc=Ogd1oex3I72BbM

Any suggestions?