Q: Server port edits on Apple SE email setup

Easier to remove and add again.

If you're struggling, check which "template" you are using to add the account. They are mostly self configuring, except for the "other" option.

Which provider and which template are you using?

Try setting your account automatically by following the steps here instead:

Add an email account to your iPhone, iPad, or iPod touch - Apple Support

The steps needed are based on the version of iOS, not any specific phone model.

I see these visual steps on their website... are you using this for help?

https://bendbroadband.com/residential/support/detail.asp?kb=100248

Sounds like you will have to contact the provider then.