Are you sure it’s because of HMWP plugin? Please try renaming hide_my_wp plugin folder name in /wp-content/plugins/ directory (you can use FTP or hosting control panel for this).
If it’s related to HMWP, then please try disabling IDS option and Trust Network option in Protection tab.
If it’s still the issue then please let us know your site’s wp-admin login details as private reply so that we can look into it further. Thanks!