I received a letter saying I need to call internal revenue service to verify my identity to process my refund
[Moderator detached this because it's not related to Venezuela taxes or similar. Do not hijack entries, if your problem is not the same or similar]
If it is a genuine letter, you should comply. If it is a scam, you should be more than careful.
Why are you posting here? This is for Adobe Stock Contributors.
The IRS is a US Government Agency. They NEVER conduct business by e-mail.
Fake emails from impostors pretending to be official entities should be reported to local law enforcement.