Happy to connect again!
We have configured the Auto-number for custom entities with the sequential number increasing by 1. User has noticed that randomly the sequences are skipped even-though we dint delete any records.
We couldn’t find anything wrong in the configuration. So we have raised to MS support. They told that
There is no guarantee that all numbers in the sequence will be used. But it will follow the
- Auto generation of value based on format.
- Increasing sequence (based on sequence format).
Then I read the docs from MS site once again. There is a note to keep in mind while you choose to use OOB auto number.
https://docs.microsoft.com/en-us/dynamics365/customerengagement/on-premises/developer/create-auto-number-attributes

Auto-number preselected at the time of record is started (when you click new button). That’s the reason for gaps in the auto-numbering of records.
If your customer is keen on the sequence to follow, you may need to build a custom auto-numbering solution.
I hope it makes sense.
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