VAT-Id not valid

I want to buy a Pro version. My VAT-ID is valid: DE251778161. But you say that the ID is not valid. What do you suggest?

Sorry, it seems that the VAT API that we used suddenly stopped working. We fixed the issue, and you should be able to proceed now. If you face any further issues, please send us a note at hello_at_mobilejoomla.com
Sorry for the inconvenience.

Thanks!
Miikka