Facebook session has expired on iPhone app?

I deleted the app yesterday so I could update the software on my iPhone. When I downloaded it again it would not let me log in to Facebook or Facebook messenger saying 'your Facebook session has expired, please login again'. I've tried logging in so many times and I've tried deleting the app, turning my phone off, I've even tried the whole thing with deactivating my account and reactivating it. Can anybody help me?

Why is My iPhone is getting hot?

When I charge my iPhone I normally am still on it or it's in my bed with me and it gets so hot. I've only had it for a month! What is going on
It's a Verizon iPhone 5s

Anyone else see the fireworks in outer space now?

Is it just me or did it just now look like 3 of the stars were spinning and spitting colorful laser beams for 30 min? Anyone know if that is some type of normal astronomical phenomenon? I recorded 30 sec of it on my iPhone, but it's not very clear. Did anyone else see that?!

Iphone 5s from T-mobile or factory unlocked iphone?

I been trying to choose which iphone 5s to buy to use for metro pcs, but I ain't sure which one to get. I would get the factory unlocked but I don't if it would work with metro. Like would would I be able to use all the functions on it. Or would it be better to go with a t mobile iphone 5s? Is one better than the other? Besides being able to use any carrier on the unlocked iphone 5s.

Which is better iphone 5s plan, contract or no contract?

I want to get an iphone 5s but i don't know if it's better to get a contract plan or a no contract plan. I would be having to pay every month with a contract and that's annoying. Yet with a contract i wouldn't have to pay that much for the phone would i? If i got the non contract i would get to pay the bill when i want but i would have to pay full price for the phone.

Which Apple app is perfect for saving battery?

I recently bought an iPhone 5c and the battery dies extremely fast. I see a lot of apps but I think all it dose is just tell me what is using my battery usage at the moment. I want a app that actually saves battery by doing what it has to do save battery.

How to get apps on iPhone to close differently?

I didn't really know how to phrase the question so sorry if it's confusing haha.
So my apps close out like going back into the app kind of or something i don't know how to describe it, but my friend has it so that his apps fade really quick when they close out. So how can I get that? His phone isn't jail broken or anything.

AT&T is charging me for data when my cellular data is off?

At&t has charged me for data I did not use. First Id like to say that I have the iphone 4s and it allows me to turn of the cellular data. I keep my phone on Wi-Fi most all of the time and always keep the cellular data off. My phone shows me how much data I have used too and It still says I have only used 553mb of data usage. My problem is I went to sleep and my cellular data was turned off. I wake up in the morning with 2 new texts saying that I have used all of my data, and on top of that I had another text that said for twenty dollars we can give you more data. Heres the kicker, they charged me the twenty dollars to add more usage all while I was asleep! Can anyone please make sense of this? I contacted at&t and they were no help insisting that I had used this data. Like I said my data still says I have only used 553mb. Before anyone says someone may have grabbed the phone and been using it, Its not a possibility.