We appreciate you clarifying this for us, LA_in_LA,
Since it's only happening on your iPhone, you may consider removing these accounts then adding them again as outlined here: If you can’t send email on your iPhone or iPad - Apple Support
"Remove your email account and set it up again
- On your computer, sign in to your email provider’s website. Make sure that all of your email is there or make sure that your email is saved somewhere other than on your iOS or iPadOS device.
- On your device, go to Settings > Mail, then tap Accounts.
- Tap the email account that you want to remove.
- Tap Delete Account.
- Add your account again.
If the steps in this article don't help, contact your email service provider for more information."
If you're still experiencing the same behavior after removing and adding the account again, feel free to reach out to Apple to investigate this further with you. You can reach them here: Apple Support
Kind regards.