I put a lien on my ex-husbands house and property for the back child support that he owes me.I have been told that I have to go to the courthouse and renew that lien ever so many years. Is this true and how often if it is true.We both live in Tennessee.

Who told you this? It is certainly possible that the rules require this. Why not ask the county clerk or recorder of deeds?

Is the figure on the lien straight forward or has there been changes to the amount?

Normally liens are not renewed, but judgements have to be.

But if in doubt, as noted check with your attorney who did the court work, and/or check with the local recorder of deeds