Autopopulating Preferred Name field as per FirstName

Summary:

We just had a customer requirement where the preferred name field should be autopopulated with firstname. I tried via Autocomplete where the logic was

Firstname == preferred name which didn't worked as expected. Tried with with Defaulting as well as Modification rule, still could not tackle the requirement. Can this req be achieved via autocomp rules? What should be the logic that should I follow?

Thanks in advance !!

Regards,

Sreeram.V

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