In the registration step, the user needs to provide the VAT number of the company as it appears in the ENTSO-E database. The VAT field can contain only capital letters and numbers. 

In case of . , / - or space and other signs, the platform will give the following error "The VAT number is invalid"

An example for approved VAT number as follow: DE123456789

If the error happens after the company already registered in PRISMA platform, please contact our Costumer Success team