Need some help please?

My daughter's deadbeat dad is behind on child support over 4000. He called me asking did I get a income tax check for 3500 back in February which i didn't. I'm uming his check got flagged due to the arrears. Child Support Enforcement told he it was flagged but they haven't got the funds yet from the IRS and the process takes 10 weeks. Well it's over ten wks and I'm getting no support from him now is there any websites i can visit or numbers I can call to get information about my particular case??