Sync two DB user sources between gateways

I have two gateways that I am trying to keep users in sync between, obviously the best method without AD would be database user sources, but when I try to attach my gateway to a user source table already created by another gateway, I get this error: INFO | jvm 1 | 2019/06/17 18:08:48 | E [i.U.Wrapper ] [18:08:48]: Error fetching ERROR: prepared statement "S_1" already exists