Hi,
I have been using GSE for a few years now and have enjoyed it a lot. However recently I have discovered while in combat I can no longer apply dots to other mobs.

For example I would use /castsequence reset=target dot, dot, dot, dot

I have looked at every macro on lazy wow macros to see how they are set up, and I would incorporate that into my macro with no avail.

It’s like the macro isn’t a resetting when targeting a new add while in combat.

Welcome to bugs in castsequence. As this is a known Blizzard macro problem it’s not something I can do anything about. You’re not going to like hearing this but I would recommend avoiding castsequence for anything you want to depend on.