WordPress Troubleshooting Support

WordPress Troubleshooting support. Looking to have an ongoing contact that can be called up to fix errors within WordPress installs. Currently over 100 sites that are all stable and working. One site though is live and working but cannot log into admin dashboard. Normal troubleshooting has failed to resolve issue (rename plugins folder, replace htacess, adjust PHP timeout settings etc). Looking for immediate support on this one issue with view to ongoing support. Hosting in cPanel. Login access is available to WordPress and cPanel. Site is backed up but care must be taken to ensure the site data is not lost as it is a woocommerce install.