Email Accounts are highlighted RED

Today when I started Thunderbird two of my email accounts are Highlighted in RED with a RED Triangle at the end of the email address. Both accounts are from Spectrum. My other email accounts from another provider are OKAY. I am not able to retrieve or send emails on these two accounts. I can get my emails from both accounts when I use Spectrum Webmail. So it looks like the account information is correct. How do I fix this?