Hi Ghada,

1. What template full name you are using?
2. If you do not have raw Helix Ultimate, but different template name - you can use that tip & file: https://www.joomshaper.com/documentation/helix-framework/troubleshooting-faq#missing-webfonts-json-file
3. Use that tip in case of: https://www.joomshaper.com/documentation/helix-framework/customization-tips#how-to-add-google-fonts-manually

this (3) method is even better, becuase fonts loads faster than from Helix.

By now it's all I can suggest, also becuase I cannot edit Helix source code.