Your browser may be using HSTS: https://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security
Essentially, when a browser visits a site at https:// it will remember that and always redirect to https:// on consequent visits, to prevent bad security situations. Unfortunately, this can be a problem during development sometimes.
If that’s the problem, you’ll need to remove your domain from the HSTS cache in your browser. It varies by browser, but in Chrome you can fix it by going to chrome://net-internals/#hsts.