Hayward Tcell 15 Chlorine Issues

I am beginning to think there is something wrong with my chlorine generator. I have a 20,000 gallon in ground vinyl pool and have been having trouble with chlorine levels since spring. I thought my cell was bad because it was starting to read lower salt levels than what was tested so I went and bought a brand new cell. Seems to be generating chlorine but dont think at high enough levels.

Main question is what ppm should the FC be when a sample is taken straight in front of the return jet with salt cell generating? Currently my pool only has a FC of less than 1ppm. When a take a sample in front of the return it reads around 3ppm when generating. It also reads around that same value with the superchlorinating feature enabled. Is this too low and might this be the source of my problem?

Salt is around 3100ppm, running at 26.3V and 7.5amps

CYA is around 60ppm