The client pays for the goods/services through the payment system. What documents do I, as an individual entrepreneur, have to provide him?

Question

Payment systems

Hello!
Help to understand the legal intricacies of accepting payments through electronic payment systems. I use the Robokassa system.
I work as a sole trader. I sell equipment and charge a monthly fee for access to my service.
The work scenario is something like this:
1) the client selects a product or service
2) replenishes his internal account on the site (through his personal account) for a certain amount. amount
3) I write off the necessary amount from his account
4) the client receives the goods, service
An important point. Clients are individuals.
And actually, the question. What are the legal subtleties in such a scheme of work? ( What documents should I provide to the client when sending the goods? What, for example, will be a confirmation of the fact of payment? Etc. )

Answer 1

1) depending on what product and service, you need a different package of documents and, accordingly, you need to understand what you specifically sell and what service you provide
2), 3) if you are not a bank or you do not have a special licenses, you cannot have accounts of your customers and keep funds on them, you should receive money for the shipped goods or services rendered, and not replenish some balance
I advise you to turn to the fondy payment, they often help their clients deal with legal issues