“Fixed” leak still leaking

[Kathy kelley]

We have a 18’ by 6’ 3 1/2 deep gunite spa. Last summer it started leaking water.
We had a leak detector company come out. They performed all the tests and determined it was leaking at the skimmer neck. They put in some temporary apoxy and that stopped the leak.
We had them replace the skimmer.
The pool was still leaking afterward.
They said it was probably the kids splashing water etc.
About 2 weeks ago it started leaking a lot and the spa lost it’s prime.
We had the technician back out.
He did all the tests again and put the temporary apoxy back in where it was leaking originally
It has not leaked since.
We assumed the company will come out and re do the work they did by putting in a new skimmer and re sealing the neck.
First, they said there was a better apoxy they could fix it with. If that’s true, there was no reason to jack hammer out the skimmer to fix the leak at the skimmer neck.
Now, they are saying they want to re check the hydrostatic relief valve. On our paperwork it says they checked it both times they came out.
We do not think we even have a hydrostatic relief valve in the spa. Checked our original paper work and spoke with the people that put in our new heater and pump. They do not think we have one either.
I think they are used on pools deeper than 5 feet, but could be wrong.
What should we do at this point? We have lost confidence in what they say.