Hi how do I report fraud on someone claiming a dependent without my permission

Go to this IRS website for information on reporting tax fraud - https://www.irs.gov/individuals/how-do-you-report-suspected-tax-fraud-activity

It depends.   If they are entitled to claim the dependent then they do not need permission form anyone.

If they are NOT entitled to claim the dependent then the taxpayer that IS entitled to claim should do so and paper file if the SSN rejects.   The IRS will sort it out and send a big, back tax,  bill and penalties to the taxpayer that claimed but was not entitled to claim (that takes about a year).