Covid Cash Out Rewards

Factfinding

I must apologise as I am new here. I need some advice as not sure if someone is trying to scam people. I thought I would come on here as I am sure there as some people who have a lot of knowledge about Payment. I would like to know if some people were sent this offer where a client sends £50 and then they would be liable for Cashback of £150. Saw a message says Cashback Processing with my account number underneath showing £150. Is this possibly genuine and if it is genuine how long did you find it took to go into the clients account.