If you are connected to the Internet through the same gateway/modem on your mobile devices as your PC (i.e. not still connected to cellular networks on your mobile) then the PC itself is more likely the culprit.
Have you cleared your browser cache ( usually F5)?
Have you rebooted your PC?
Have you restarted your gateway/modem?
How is your PC connected to your gateway/modem, wire or wirelessly?
What happens when you try to go to the same site on your Wi-Fi connected mobile as your PC?
Let us know more and we can better help you.