Consider the following scenario:
In Microsoft SharePoint Online, you save a subsite as a template by selecting the Save site as template option in Site Settings.
The template was saved from a site that uses either a Team Site template for which the Community Site Feature is active or a Community Site template.
You use the template that you saved to create a subsite.
You create a category in the community and then click the tile for the category.
In this scenario, you receive the following error message:
Cannot complete this action. Please try again.
To work around this issue, create sites from a standard SharePoint Online template when you plan to use community categories. Categories will function correctly on a site that wasn't created from a site saved as a template.
This is a known issue in SharePoint Online.
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