Random deposit from a stranger

Description

I received two separate random deposits from a stranger. TandK Enterprise, it had a website that took me to a page that legit looked like a scan about a weightloss book, and there was an email. I got first deposit for $9 and 2nd for $8 one day apart. I was confused, i sent an email to the person asking what it was for. They said « I apply. I send to wrong person. Can you refund please » there is an obvious language difference from the incorrect grammar. I didn’t email back and I didn’t refund the money. I started searching for similar scams. I’m afraid if i refund the money, it will somehow give them access to my account or my linked bank account .. anybody else experience this? What should I do?