"We could not confirm that you are you" (Verification failed)

[Ventegodt]

In spite of having completed my 4-digit verification process on my phone, I get the message "We could not confirm that you are you", which disables me from making any transactions. 

What do I do in order to solve this???

[kernowlass]

@Ventegodt

Only customer services can help you with account issues, so your best bet is to phone them.