Some account assignments failed to get assigned when running the Mass Assignment Rules from the Territory Utilities. An error occurs: unable to obtain exclusive access to this record or 200 records.
A process in Salesforce is editing the record at the same time. Some common causes are:
- Sharing Rules are being calculated.
- A picklist value is replaced or replacement is in progress.
- A custom index creation or removal is in progress.
- A user is already editing the same record that is being accessed.
Concurrent Apex jobs
Concurrent batch jobs
Custom integration job editing the records (Usually that is bulk API related process)
Rerun the Territory Utilities.
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