What is the ruling on money earned from promoting the sale of followers and likes online, and is it necessary to dispose of the earned money that has been spent or used to purchase a phone, and how does one who did so out of ignorance of its prohibition repent?

You are not liable for anything concerning your previous work in promoting the sale of followers and likes, because you believed it to be permissible while you were working. What a person earned before knowing its prohibition, there is no sin in benefiting from it, based on the Almighty's saying concerning money earned from usury: "So whoever receives an admonition from his Lord and desists, he may have what has passed, and his affair rests with Allah." Furthermore, the questioner was dealing with owners of commercial pages so they could benefit from promoting their businesses, and this involves a considerable benefit for the buyer.