THIS PLUGIN WILL BREAK YOUR SITE.

User Role Editor does not include the “Revert” permissions function. If you used the “Reset” one, it shows the strong warning:
“WARNING!? Resetting will setup default user roles and capabilities from WordPress core.
If any plugins (such as WooCommerce, S2Member and many others) have changed user roles and capabilities during installation, those changes will be LOST!
For more information on how to undo undesired changes and restore plugins capabilities in case you lost them by mistake go to:?https://role-editor.com/how-to-restore-deleted-wordpress-user-roles/“

More, in order to enable the “Reset” button, you should to manually input the text “Permanently delete all custom user roles and capabilities”.

So you should clear understand what do you do before use the “Reset” button.

“So you should clear understand what do you do before use the “Reset” button.”

That is your fault. I use hundreds of plugins, if your instructions are not clear, then that needs to be addressed.

We didn’t have WooCommerce or any other member permission related plugins.

Right now, my ‘Contributor’ is broken and they can’t access anything.

WooCommerce was mentioned just as an example. Roles reset affects any user role, updated/changed after WordPress installation. If you know what plugin changed your contributor role, you may try deactivate/activate back that plugin. The most of plugins (we may mention the same WooCommerce again) restore their user roles/capabilities on activation. If you have a stage/development copy of your site, you may look the older list of capabilities in contributor role their and restore them manually.

THIS PLUGIN WILL BREAK YOUR SITE.

i totally agree with you, that happened to me because this plugin,, only this plugin prevent even admin login to the backend and destroyed a work of 6 months , but the backup saved my life.