First, check the privacy settings of the original story. If it's set to not allow resharing, there's not much you can do. However, if it seems like it should be shareable, try refreshing the page or logging out and back in. This can sometimes fix technical glitches.
It could be due to the terms and conditions of the platform. Maybe tagged stories are meant to be personal or for a specific group, and resharing violates the rules. Also, if the story contains copyrighted material or is reported for some inappropriate content (even if it's not actually inappropriate), resharing might be disabled.
It could be that the platform has certain rules or glitches. Sometimes, technical issues can stop you from resharing. Also, make sure your account is in good standing and not violating any terms of use.
There might be several reasons. Maybe the story has restricted sharing options, or there could be a problem with your account settings or the version of the app you're using. Try updating the app to see if that helps.
It could be that the stories you're trying to reshare have some restrictions placed by the original posters or the platform's rules. Sometimes, certain content is marked as not sharable.