I have been using the yahoo mail app for years to access my btinternet emails. I have the latest iOS and the update to date yahoo mail app.
A few days ago I changed my btinternet email password and now logging on to the app it directs me to a page saying:
If you're using an internet browser you may be using an old link go to https://www.bt.com/email - ( this link takes me to the bt mail log in page)
Setting up email?
It looks like you have selected 'yahoo' when setting up your email, please select 'other' (it only shows Gmail, AOL and outlook) and then enter your email and password.
Using the Yahoo mail mobile app?
Sorry we don't support new setups via the app anymore
Very annoying as I have contacts that are synced with my phone.
They're obviously tightening up security on these things, probably why the Yahoo app no longer works with BTYahoo. I was unaware it did anyway. Why not use the iPhone mail app? Same email address. Mine works OK.