Salutations Ffgpedro,
Here is an article with some steps to take if you’re unable to receive emails on your iOS device. If you can't receive email on your iPhone, iPad, or iPod touch
The first steps that article suggests, before going on with additional troubleshooting are:
Before you begin
There are a few things to keep in mind and check:
• When you make an iOS or iPadOS backup in iCloud or iTunes, it backs up your mail settings, but not your email. If you delete or change your email account settings, previously downloaded emails might be removed from your device.
• Make sure that your device is connected to the Internet.
Check with your email service provider to find out if there's a service outage.
• If you can't access your email, or you can't send and receive messages with your @icloud.com email address, learn what to do.
Thanks.