Under 31 U.S.C. 5330 and its implementing regulation (31 CFR 1022.380), money services businesses (MSBs) must file an initial registration report with FinCEN, renew their registration every two years, re-register under certain circumstances, and maintain a list of their agents.
The latest form for Registration of Money Services Business - FinCEN Form 107, 31 CFR 1022.380 expires 2023-06-30 and can be found here.