Why does my iphone6 not accept my mail password?

I have had the same email address and password for years,
it works fine on my Imac and macbook air, it will work fine on my iphone6 for a few weeks but every so often my iphone rejects it.
I have tried deletring the account in settings/mail then resetting it, but it still get the same message
"Can't get mail"
The username or password for mail.btinternet.com is incorrect.

It is not incorrect. I use it all the time

Will my explode explode when left vibrating all night?

I can't sleep tonight its 1:58 am here. My iPhone 4 keeps on vibrating non stop! I'm afraid maybe it will explode later, no one can know.

I tried stopping it by holding home + lock button that didn't do anything, I don't have appropriate screwdrivers to pry open the back of my phone. So my only choice is to bring it to a professional later as soon as the nearest mall here opens.

Also I can't switch on the phone, there's also no battery icon when I charge it.

Hope I can sleep peacefully when this scenario's done. Thank you in advance for your response though.

Added (1). Nevermind. 2:50 am, hooray I no longer hear the annoying vibration! I can now sleep.

Order processed: ready for UPS hasn't updated in 5 days?

I bought a gold Iphone 6 at the AT&T store last week, and the estimated delivery was 3-5 days later. It said origin scan, then departure scan, then ready for ups. It shipped 5 business days ago from a city less than hour away from me and I haven't gotten any updates. It seems like it shouldn't take that long to get here or at least any updates of it moving. I also has an "unavailable" delivery date, and at first it said "in transit: on time" now it just says "in transit" if that makes a difference. I'm just not sure about anything with UPS so anything helps, thanks I'm advance.

T-mobile doesn't get my information in their system?

So i ordered an iphone 5s by the internet and after i put all my information they sent to me to a link that said that i needed to call to complete my order. They gave me an order number and i called. After i gave them my order number they said they couldnt find the information in their system and that i had to wait 2 hours. However i already waited 4 hours and they still don't get my information in their system. What do i do?

I sold my imac and wish I didn't! Any way I can get it back?

I had a 27 inch imac that I loved but i got excited about having some cash in my pocket and the new iPhone 6 plus so I sold my iMac for $1150 and now deeply regret, any way I could buy back this item, it was a physical sale a lady in town picked it up, I've been thinking about sending her a message what do you guys think what can I do, I desperately would do anything for it back at this point.