Hi Luis,
Regardless of the UK law or any law for that matter, the type of business you working with has a specific Industry code (MCC), which determines the type of business and category.
Based on that, your merchant probably would be considered a “High Risk” merchant, which automatically is not qualified for any merchant account under processing companies or partners that can board regular/most common accounts.
That said, you will have to look for a Merchant Account Provider who specializes in High Risk accounts. A quick google search will give enough information to get started, but as a quick reference, Electronic Merchant Systems (EMS) , is one of them.
I hope this helps you understand a little better the payment processing industry.