Email issue on iPhone 14 Pro Max iOS 18.01

Since updating my iPhone to iOS 18.0 I have been having an issue with my Comcast email account. I have deleted the account on my iPhone and have re-added the Comcast account to my Mail app. When I send an email account from my Apple email Address to my Comcast address. It goes through properly. However, when I send an email from my Comcast account to anywhere, I get an error message and the mail will not send. The era continuously asked me to input my Comcast password. I I have have tried over 20 times inputting my correct password. However, it appears that the Comcast system is not accepting it. I have no problems logging into the Xfinity iPhone app using the same password. Can you tell me what I need to do?