I asked about the parameters because these fish (both rams) are highly sensitive to such things. The blue (common) ram [in any of the varieties, they are the one species] will survive best in water that is reasonably close to that in which it was hatched/raised. This is unique among fish; most species require (to some degree) water similar to their habitat, but this ram should manage if the water is kept close to what it was raised in. The Bolivian is different, it requires water close to the habitat regardless.
The blue ram needs warmth; 80F (27C) is absolute minimum, but it will be stronger at 82-86F (28-30C). This species has a normal lifespan expectancy of 4 years, maybe 5, but it will never live close to that at cooler temperatures. However, the lower temperature will not kill it that quickly, it is a slow weakening of the fish's physiology and metabolism.
The species is highly susceptible to any problem with water conditions aside from the above. It cannot tolerate nitrate (all cichlids have significant issues with nitrates even close to 20 ppm). It would be impossible now to assess what may have been the problem with prior fish. They need careful handling, with no sudden changes in water parameters or conditions. There may have been a problem at the hatchery, the supplier, or the store.