There is an algorithm in place that tries to detect commercial use. It's not based on download amounts. It takes into consideration other aspects like number of connections, type of connections, and of course amount of traffic and some other masala. It's still work in progress and obviously can trigger false positives. Sorry if this was your case.
Excitel connection is purely for single household and of course many are abusing this policy and there is an attempt to catch and stop them because this kind of usage loads the network unnecessarily, creates peaks of traffic and this itself spoils the service for rest normal users. Network is planned and designed to sustain traffic levels that are based on home usage (no matter how many devices) and when misused this not good for all.