Suppliers of electronic services, such as Whatagraph, are obliged to charge VAT on the service. If the purchaser of these services is a taxable person, then in certain circumstances, it is the customer, rather than the supplier who must account for the VAT. 

For this reason, the supplier may ask for the VAT identification number of the customer, so that he can confirm whether it is he who must charge the VAT or whether the customer himself will account for the VAT. If the customer does not have a valid VAT number, then the supplier will charge VAT.