my retirement accounts are not accepted

I have added 2 paypal accounts, one company and one personal, and none of them is accepted, it asks me to have a certificate letter/company registration, but I don't know how to get that or how to process it.

I am not a company, I am an illustrator who wants to start selling commissions through pph, I don't have a big income, and I am not registered as a company.

how can I solve this, in customer service they don't answer me, and I have a client waiting to close the order (he already received his work, but the order is still active).