Email on Galaxy S8

This is to kind of set up the scenario: I changed my password a couple weeks ago but my laptop is still able to download with the old password. Jump to yesterday 1/2/2018 and my phone (Galaxy S8) said that it could not connect to server. I typed in the old password and it wouldn't connect. After a bit of frustration I deleted the account off my phone and tried to set it back up. Now I get "The username or password is incorrect or POP3/IMAP access isn't turned on for this account. Check your setting or contact your service provider" How do I fix this and get my email back on my phone using the current login and password for my primary account? I have had this account for about 17yrs and is my primary use account. I know it's kind of 2 problems in one but any assistance would be appreciated. Thank you Mike