I purchased a prepaid sim from store. When I tried to Activate it using my Indian passport they said it is not possible to activate it online. so I have to take it to Deutsche post. But the problem is there also they cannot scan my passport. So what

I purchased a prepaid sim from store. When I tried to Activate it using my Indian passport they said it is not possible to activate it online. so I have to take it to Deutsche post. But the problem is there also they cannot scan my passport. So what should I do to activate my sim.