SQL Server on RDS

I accidently deleted the rds admin user on a database (not the server instance). If i issue USE [database_name] I get Msg 916, Level 14, State 2, Line 1 The server principal "rdsadmin user" is not able to access the database "database_name" under the current security context.

Now I can't delete or restore the database. How do I delete it? All other databases are running fine and the rds admin have access.