Plumber issue- hired plumber and now trying to overcharge

[Tammy M.]

We hired a plumber (that we have used for years) to fix a tub spout leak and toilet repair. They fixed the toilet with no problems. They installed a new cartridge for the tub but it was still leaking. Said they would have to come back out and tear into the wall to fix the valve, which was going to run over 1k. When the 2nd plumber came out (with the same company), he said the cartridge was not seated due to there being some calcium that needed to be scrapped off and no new valve was needed. 

Now it is fixed and not leaking anymore but the plumber wants to charge us twice for the repairs although the second plumber just fixed the first plumber's mistake.  We have already talked to the owner and insists that we have to pay for both tub spout repairs. We do not feel like we should have to pay for the 2nd plumber fixing the 1st plumbers mistakes. Do we have any recourse? What should we do?