HTC Desire 826 - How to solve Wifi connectivity problem?

Hey,
I got the HTC desire 826 a couple of weeks back and updated it to the 6.0 Marshmallow OS. After the software update, it stopped connecting to my home Wifi. It'd either say "Disabled" or "Connection Failure". I did a factory reset and it started to work fine (for about a week). Last night after the battery died, I plugged it in for the night as usual and upon turning it on this morning, the same problem appeared. It won't connect and I've done all the basic things, I've tried rebooting it, resetting and rebooting my router, turning on aeroplane mode, resetting my wifi settings etc. I love the phone but I can't keep on formating it every week.
Is it some software issue with this model specifically? Why does this problem keep recurring? How should I fix it? I really need Help.