I need to create a unique document number field using a string with combination "APXXXXXXXX". AP + sequntial# and it will be auto generated, unique and end user can only view it but cannot change it. Please note I am using SharePoint list.

I need to create a unique document number field using a string with combination "APXXXXXXXX". AP + sequntial# and it will be auto generated, unique and end user can only view it but cannot change it. Please note I am using SharePoint list.
Hello @Fbaloch ,
You can achieve this using flow.
- create an automated flow- when an item is created
update the auto increment field with required expression - update action
Try referring below url
Thanks.