Can’t use Facebook in Safari on my iPhone

I have an iphone5 and For years I’ve been logging onto Facebook thru safari and not using the app because it takes up too much room on my phone. Now if I try to open my Facebook page on my phone using safari, it wants me to set up my account all over again and add friends as if it’s a brand new account.

But on my iPad , where I do use the app , it works as usual.