Is this a new site, site copy? What version of PHP are you running... if you're running 8+ try switching to PHP 7.4... the latest version of Acronym has some PHP 8 fixes
SEARCH the forum first! These boards are rich in knowledge and vast in topics. This includes searching just the 'Solved' forums, using Google, and using ChatGPT
Please take a backup and reinstall the Gantry plugin by downloading it from here and using the Add Plugin > Upload feature... WordPress should display a success screen where it says it "upgraded" it.
SEARCH the forum first! These boards are rich in knowledge and vast in topics. This includes searching just the 'Solved' forums, using Google, and using ChatGPT