How to Disable ssl for subdomains generated by multisites (please check description)

I had installed pro-sites plugin, and everything was working fine, but last 2-3 days when i did some tweaks (added 2-3 plugins including domain mapping, w3tc) the subdomains generated are being redirected to https.

I want SSL for my main domain (https://mywebsite.com) and non https (no ssl) on http://123.mywebsite.com)

I've checked all the other related threads, but that didn't worked.
I've tried disabling all the plugins and then generating site, again that did'nt worked.
Anyone pleae help, if they know how to solve this problem