Stuck on Welcome to Mail screen

I deleted my email from my iPhone as it wasn’t working properly. I went to add the account back, selected yahoo, input user and password, it then takes me to a screen that has toggles for mail, contacts, reminders, calendars and the screen is spinning like it’s going to complete the set-up, but then takes me back to the Welcome to Mail screen (with all the mail providers) and doesn’t add the account. I do, however, get an email to my yahoo account that says the account has been added through iOS. I have restarted my phone, deleted and re-installed the app… nothing seems to work! HELP!!!!