According to new legal docs, obtained by TMZ, Sam's wife, Hannah Lee Fowler, asked the court to dismiss the divorce case last month, and a judge signed off.

Remember ... Hannah cited infidelity when she originally filed for divorce back in February, but she quickly withdrew her petition and refiled it in a different county in Tennessee.

But, this time around it looks like the divorce is really being called off.

There's more evidence Sam and Hannah are giving their marriage another try ... he's been wearing his wedding ring again.

Sam was NOT wearing the band during a performance in March when the divorce was still working its way through the courts, but he was rocking the ring last week on stage in Florida.

And, get this ... witnesses say Sam and Hannah have been spotted together recently, walking their dog in Franklin, TN.

They have a pretty good reason to reconcile ... Sam says they are expecting a baby girl at the end of the month, which would be their first child.

TMZ broke the story ... Hannah filed for divorce back in February. In her divorce docs, she said Sam was "guilty of inappropriate marital conduct" and "adultery." She asked the court for primary custody of their future child and alimony.