I had de beta of IOS 14 and later I updated my iPhone but I still recibed notifications to update a iOS 14 beta and I don’t have the beta anymore

if you're running 14.2, you did not uninstall the beta software. 14.1 is the latest public release.

You probably just deleted the beta profile, which is not the same thing as removing the beta iOS version.

How to uninstall iOS beta software - Apple Support

see the section Remove the developer beta by restoring your device

we've been seeing lots of these posts tonight.. everyone seems to be running 14.2 beta

• you can use the feedback app to report the issue
• you can wait it out and hope that Apple has a fix for it soon
• you can uninstall the beta software and go back to a public release

How to uninstall iOS beta software - Apple Support

Yes, you should be able to install the next official release of iOS whenever it comes out.

Until then you will have to live with the issue if you don't want to restore to a pre-beta backup or don't have one.

Go to Settings > General > About, what does it say for Software Version?

I uninstalled the beta, I’m running 14.2 and I keep getting the same message

Wow you are exactly right! The only way to uninstall would be to restore my device!?

Precisely, as you were warned when installing the beta.

Disaster! If I wait until a new software update comes out and install it will that work?

It is what it is! Thanxs alot