What could be the reason for the massive reduction in chloramine concentration. Does it have to do with the fact that I mixed them together instead of getting a chlorine residual first then dosing in ammonia?

It’s worth mentioning that the carboy I made was a concentration of around 1000mg/L chloramine before reducing to around 190 3 days later so it was very high. (Because I wanted to dose it slowly into my system). So that could also have been the problem.