Hi guys the problem is on contact form 7, roll back to 5.5.1, here´s the link, scroll down to the bottom of the page and choose that version.
https://wordpress.org/plugins/contact-form-7/advanced/
On wordpress install the version(5.5.1) it will say that there´s already the newer one, nevertheless proceed to this version.
There you go, now you can save!
PS: Disable automatic updates until this plugin is updated!
Happy coding!
Thanks to the developer it´s an awesome plugin, I´m just here helping a little bit.
JC
