Hello,
Thank you for contacting Rank Math and sorry for any inconvenience that might have been caused due to that.
This feature will only work on images that are added on the main post content editor or when editing a product. It will not work for images added by the theme, for this you will need to manually assign the ALT tag descriptions.
Looking forward to helping you. Thank you.
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Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.