Could be this https://www.cloudflarestatus.com/ Also could be a false positive
Looks like something broke https://downdetector.co.uk/status/shopify/
Yes its down from last 10min
Hi folks - thanks for flagging, our team are investigating this. The best option right now is to keep an eye on the status page.
Sure thing @Liam-Shopify Just seen the X threads, looks like it is more than just Shopify this time too. Feel free to mark as resolved as it has been picked up 
We made a handy free tool that notifies you when Shopify reports incidents if you’re interested. You can subscribe at https://shopstatus.io
This error has been going on since end of May but today this is a huge increase!
As a thought, the message here for “This store does not exist” is very not good for customers and worrying them. Imagine making a big purchase and wanting to see about it in your account… Imagine the panic and thought going through your customers head.
I vote that it should say “technical issue”
It’s very bad. Im a shop owner and I’m concerned my customers may think im now out of business. Im completely lost for words and shopify have not sent a email. Ive had to search online to find out what is happening. My heart sunk when i saw this.
I noticed a server alert and found that a large number of Shopify GraphQL API endpoints were returning 404 errors. I started wondering if the GraphQL version I was using had been discontinued or removed. Fortunately, it turned out to be just an issue with Shopify’s service itself—it has since been restored, and the massive 404 errors have disappeared.
It appears for me that the front ends of sites are coming back up and admin access is now back too @Liam-Shopify also partner portal and dev portal are back for me in the UK. Thanks for reporting and thank you for the teams response to this.
I would like to suggest changing the “Store does not exist error” to “something else”, though coming from a server admin background and Magento2, I know could take “some work” for creating a “custom” error page.
Thanks again
I would like to second this request. As of now there is no way to differentiate between “Shopify is down” and “Store is Inactive”.
