reindexing keys in postgres

["Harpreet Dhaliwal" <harpreet.dhaliwal01@xxxxxxxxx>]

Hi,
Lately i was searching for a way I could reindex all my keys. Primary Keys in particular. 
Really didn't find any manual that could guide me through.

Reason i wanted to reindex my PK is that whenever i insert a record in the table, even though that record is unique, i get an error saying violation of primary key.
So i thought of reindexing my keys.

Can anyone give me pointers for the same

Thanks,
~Harpreet