Each vSphere Replication appliance going to be needing own database, you cannot share same database with two VR appliances.
Possible solutions would be (you will have to find appropriate documents depending upon your VR version)
1) Remove additional VR appliances apart from the one which was your first VR appliance
2) Restore DB from backup which was taken before you configured second VR to point it to existing database
3) Let your first VR appliance carry on using it
4) check if things are back on track
5) carry on deploying more VR appliances with their dedicated databases