Financial Records from Wage Garnishment

Hi. Thanks in advance to anyone that responds. I had a wage garnisment issued against me - for a debt I owed, not debating that point. The payments came out of my check and stopped in May when I believed it to be completely paid off. Now 4 months later they are deducting from my check again and saying that there is still a $700 balance. The "law" firm refuses to provide me with any kind of financial recordkeeping showing when they received my money, how it was applied, how they are applying the interest, etc. Is this legal? Am I really supposed to trust their word on my account balance? Is there a way that I can force them to provide me with this information? If they cannot provide this information, how am I supposed to believe that they are keeping an accurate record of the amount I still owe? Thanks.

You can dispute it, file in court and subpoena all records if need be. You could probably even use small claims.