Issue might occur when performing an operation on an unnumbered interface (such as wrp, vpnt, etc), or if an unnumbered interface (such as wrp, vpnt, etc) is affected, in an environment with configured Dynamic Routing and ECMP (equal cost multipath).
Issue occurs after an operation that makes a dynamic routing protocol running in the Security Gateway to recalculate its routes and consider a route with more than one next hop - such as when an unnumbered interface is added/removed.