Connection speeds are a joke

I'm on Rain 5g, when I got it it worked fine for about 3 weeks thereafter speeds have been very slow, I can't even stream without it buffering multiple times per show... for the past 5 days the highest speed I've got on the Rain speed test is 5mbps. This is ridiculous, I'm not getting what I'm paying for! And please don't tell me to move the router around because clearly that's not the issue. Rain needs to sort out their network capacity asap, I'm switching to fibre next month if this doesn't get resolved.

By the way I'm typing this complaint using my cellphone's service provider data plan because the Rain WiFi Internet connecton is so pathetic even Hellopeter.com was taking forever to load!