Removing temporary tags causes reprocessing a ticket

Hello,

I have a set of triggers, it could be pictured as follows:

• if the `T` tag isn't set and the `C` condition is true, then do `D1` and add the `T` tag;
• if the `T` tag isn't set, then do `D2` and add the `T` tag;
• if the `T` tag is set, then unset the `T` tag.

The `T` tag is a temporary tag that is being set only when `D1` is done. The `T` tag prevents `D2` from being done, because in certain case (when `C` is true) I need only `D1` to be done, but I don't need `D2` to be done if `D1` is done.

So far, so good.

The problem is that `D2` is being performed too. :-( I looked into events and I see the following:

• that `D1` is done;
• the `T` flag is set;
• the `T` flag is unset;
• the `D2` is done;
• the `T` flag is set.

I can't get why the last 2 steps are being made. Unsetting the `T` flag is the very last trigger in my set of triggers. Why does Zendesk reprocess this ticket again? How to prevent that?

Thanks in advance for any clues.