Email segments, product tags not working

[LocoShop]

We had a segment set up which picked out 147 of our customers who had bought products with a specific tag.
Recently this has stopped working.
Sometimes it shows that there are 147 members of this group, other times none.
When I want to email this segmented group it just greys out.
I also did an order search by the tag and nothing came up, but the products all clearly have the correct tag.
Any help appreciated.

[Small_Task_Help]

Hi,

Hope following will help

- Check tags are correctly applied and consistent.
- Review Segment setup
- Check there are no sync issues or search filter errors.