How to fix “Sorry, you are not allowed to access this page.”

Using WP-CLI

If you see an empty ROLES then it is

wp user list
+----+------------+--------------+--------------------------------+---------------------+---------------+
| ID | user_login | display_name | user_email            | user_registered                | roles |
+----+------------+--------------+--------------------------------+---------------------+---------------+
| 1  | admin1     | admin1           | [email protected] | 2018-06-19 17:00:02 |         |
+----+------------+--------------+--------------------------------+---------------------+---------------+

So add admin right for this user:

wp user set-role 1 administrator

Check it, should be good now:

wp user list
+----+------------+--------------+--------------------------------+---------------------+---------------+
| ID | user_login | display_name | user_email            | user_registered                | roles |
+----+------------+--------------+--------------------------------+---------------------+---------------+
| 1  | admin1     | admin1           | [email protected]
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