Solution:
Hi Everyone,
I managed to fix this! Since the WordPress 4.9.7 update where many people were getting errors, downtime etc, I pinpointed the problem and the error sits inside your database. Firstly, backup your database. Always be safe than sorry!
Then, I disabled all my plugins via my hosting (Not within WordPress as no access was available due to the user-role errors)
Now, using phpMyAdmin (Or you own equivalent) and clicking on your database, you want to open a new SQL Command. You can do this by clicking the SQL tab at the top.
Next you want to put this line of code as the SQL command which will select all from your wp_options table where the option name is equal to wp_user_roles:
select * from wp_options where option_name='wp_user_roles'
Now you will need to edit the option_value by double clicking in the box for that attribute, remove the current user roles that are messed up, and replacing with new roles that actually don’t mess up your site! For me personally I used this:
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The reason it is so long of a user-role code is due to the amount of plugins that are being used on the website I have been working on, although this may differ for others websites. But feel free to give my code a try as it may fix yours also.
If not, then feel free to post a comment as I am still happy to help you resolve this, as I know how long it took me to resolve it myself!