I am getting below error when I try to edit any page
You have exceeded the maximum number of users for your license. You will still be able to view content, but in order to create or edit content, you must reduce the number of active users in the installation.
There are two ways to reduce the number of active users:
To disable or delete a user, visit the Users page then search for their name. After following the appropriate link you can choose the 'Remove' or 'Disable' option.
This is exactly what it says - you have added too many users to the groups that control the "can use confluence" global permission, and gone over what you are licenced for.
You have two options:
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