Website works on LTE but not WiFi?

Hi there, 

I just had the Grand Opening of my in-person store and now people are saying they can't access the website. I've gone through all possible reasons for this that I can decipher with the help of my dad who works in a field that specializes in issues akin to this. I can get to my website on LTE (as can other people we've asked to test it) but it cannot be accessed using WiFi. It displays a server not found message when that is tried.

I want this to get fixed as soon as possible as I want people to be able to find the information they need within the window of time they find out about me. If there's anything that can be done or even just a diagnosis of the issue, that would be greatly appreciated.

I have had the same issues and @squarespace are useless as not enough chat agents.  Apparently they are able to access via google chrome but not other softwares.  It is 100% an issue in accessibility! No solution found as yet!