Pre Paid Credit Card or not

[777bet]

Hi,

So by definition, a prepaid Credit Card is a Credit Card, but for UK Gambling purposes, what is it? credit or Debit card?
Some sites will not allow deposits as its a Credit Card, some will as they say its a Debit Card.

I ask as I made a rookie mistake at the weekend and am having a "discussion" with a complaints team, would be great to have others thoughts on this.

Thanks