Steps to reproduce:

1. Create template with item and trigger.
2. In trigger set fields:
   OK event closes - All problems if tag values match
   Tag for matching - i_am_matching_tag
3. Create autoregistration action with operation - Link to template.
4. Turn on server and agent. Wait till host with item and trigger is created.
5. Turn off server and agent. 
6. Unlink template from created host.
7. Check created trigger. Tag for matching field is - i_am_matching_tag.
8. Update templates trigger.
9. Change Tag for matching field to - updated_tag
10. Update hostmetadata in zabbix_agentd.conf file.
11. Turn on server and agent.
12. Wait till template is linked to host.

Result:
Check Tag for matching field.
There is still old value - i_am_matching_tag
Expected:
Should be changed to - updated_tag