I have been allotted two PANs. Which number should I use?

Keeping two PAN is not a genuine practice.

You may retain any one of the numbers and surrender the other.

You will be required to write a letter addressed to your jurisdictional Assessing Officer to surrender a PAN mentioning the reason.

To find to your AO, click here: https://incometaxindiaefiling.gov.in/e-Filing/Services/KnowYourJurisdictionLink.html