If OSPF neighbours are stuck in two way state what could be the reason?

OSPF routers on multiaccess segments sync their databases with their Designated Router (DR) or a Backup Designated Router (BDR) only. The OSPF status between two routers transitions to Full only if at least one of them is a DR or a BDR.  The state remains Two-way between a pair of routers if both routers are drothers.