Customer Ip Address Seems Blocked

Had a customer call and tell me the website had been down for him for 2 days. Of course it wasnt down, and after I got him to log off his wired lan connection and log in using his cell/mobile provider network the site worked.

He was using his phone, and I asked for his ip address to see if it was a blocked range in config firewall, and it wasnt, His ISP is Virgin broadband, and I am just worried a large reange may be blocked somewhere.

Anyone have any experience of this that could shed some light. DO I speak to my host maybe to run some checks.

Thanks

John

Did you check access restrictions module?

https://docs.cs-cart.com/4.7.x/user_guide/addons/access_restrictions/index.html

I did , and it isnt installed

to see if it was a blocked range in config firewall, and it wasnt

Did you check it with this command?

iptables -L INPUT -v -n | grep "1.2.3.4"