How long does the mother have to wait to refile for child support? Father lied and the judge believed him.

How did he lie?

I don't know where you are. In NY the rule of thumb is greatly changed circumstances or 6 months. If the Judge believed him recently, why won't the Judge believe him now?

ANY question on law needs to include your general locale as laws vary by area.

If you can prove that he lied, then you can file an immediate appeal. Otherwise, it will depend on local laws.

The issue appears to be, you did not have evidence to prove the case against him, so judge believed him. If you can get evidence to prove it was lie, there should be allowance to refile

OP should move to reconsider, (or for new trial, or whatever it's called in the jurisdiction), supported by affidavits which strongly prove that the witness lied. The window of opportunity in which to do this is very short (usually a matter of a few days) and it is up to the judge.