Account definitions not getting assigned on time

We have deployed One Identity Manager 8.1.4
We have 3 types of users Employees/Contractors and Partners.
Based on the employee type, User gets respective dynamic roles like Employee / Contractor / Partner.
After this role is assigned, user should get respective Account Definition those are associated with the dynamic roles and their accounts should be created.


Recently, we started facing problem, after successful assignment of dynamic roles, account definitions are not getting assigned immediately - record is inserted in PersonHasTSBAccountDef at any random time.
In fact there is a difference in XDateinserted for record in Person and PersonHasTSBAccountDef table. The users on-boarded yesterday morning are getting account definitions today morning. Screenshot attached for reference.
The Process "Created by QBMDBQueueProcess: fire event Assign for object type PersonHasTSBAccountDef" is getting triggered at any random time after the user on-boarding and role assignment.

Till then users do not get any access in the organization and neither we can manually assign account definitions. The property IsNoInherite is set to False. This problem is faced recently for all types of users.

In system Journal I can see only one repetitive error which I assume is not related to the problem we are facing.
Error:
(execute slot single)50000 0 re-throw in Procedure QBM_ZUpdateStatistics, Line 415247 0 detected in (SRV=DBHOST, DB=DBNAME) Procedure sp_updatestats, Line 1515247 0 User does not have permission to perform this action. DBQueue Processor 4/14/2022 4:03:27 PM DBHOST QBM_PDBQueueRunner

Appreciate any help on the same.