if their bank a/c is on your return it's going to go to them.   did you agree to use your stimulus payment to pay their fee $1200?

if not, you may have been scammed 

unfortuneately the IRS phone lines are down due to corvid 19

this is the iRS website where you can update the bank info but it isn't functional yet (filer side)

https://www.irs.gov/coronavirus/economic-impact-payments