For some reason my website www.chicomputers.nl is down on a few of my devices. This website is connected to Cloudflare. using a different browser gives the same error, this happend also a month ago for a few days and then it worked again.
I also have www.chicomputers.eu that is hosted at the same provider, this one those not use Cloudflare and works fine on all my devices.
I believe Cloudflare is blocking my devices however i dont know where to look to check what might be going on.
The screenshot you shared disproves that hypothesis. You are most likely having local resolver issues. Start at layer one and work your way up. Similarly, start with the device having trouble and work your way through the entire circuit. Check its own DNS cache and move upstream.
So therefore, it is important that you ping/tracert to all the addresses you’re finding yourself, by using the nslookup command, as you may not be seeing the same IP address(es) on your location, that I do on mine.
if I had issues from France, I would for example be running the ping/tracert command to all the four addresses: