hi suma!
unfortunatly no billig system works. there's is no posibility to deposit any money.
I think and read, that many user have the same problem. I will contact free-kassa support, but I don't think this will solve the problem. even the link from your website to free-kasse is wrong and changes the billing system.
maybay you should have a look on it, I'm sure it is also in your mind that you will get some money, or am i wrong ...?