Safari won't load certain webpages but Firefox will
HI
I wonder if anyone could help. I have recently got married so changed my account on my Mac creating a new username and iCloud therefore deleting everything from before which was fine. I have tried to log on to a website that i always use www.tes.co.uk but when I tried to log on it won't let me it goes on to a blank white page saying loading but never does. I have to completely close the internet page as it won't let me then go onto a new page. However it does work when I go onto firefox. It works on my iPad and iphone as well so why not safari? I've tried clearing the cache, deleting the history, resetting safari, reset my wifi but still no luck. Can anyone help? I have safari version 8 and MacBook Pro Yosemite 10.10.5
MacBook Pro, OS X Yosemite (10.10.5)