How can I find out who has claimed my kids on their federal taxes for last two years?

i had to gather info to prove my kids lived with me last year and the irs claimed they would red flag my kids so it wouldnt happen again but it has and i need to stop this how can i stop this or find out who is doing this is this id theft

Contact the IRS. provide the social security numbers of your kids and they will have to give you the info on who claimed your kids.

that is not true. I called the irs and they wont give the names of the people who claimed my kids.