Error code in creating a new query in Access

[kastaman]

I have a DB which has a query for each dept and a form from that query for data entry.

I need to create a new query for a report but I'm getting the following message:
"The changes you requested to the table were not succesful because they would create duplicate values in the index, primary key, or relationship. Change the data in the field..........."

What do I need to do here?
I checked the table and none of the fields are indexed or have a primaty key.

Any help is appreciated.

Merci,

Kastaman