When joining a world, Tag minecraft:tick don't work unless reloading.
(maybe other tags will also appear the problem but I don't have time to test them)
- Create a new world, and add a data pack with a test function (just include a say command) to the world, and add the minecraft:tick tag to the function.
- Run the reload command and make sure the function can be executed correctly (spamming).
- Quit to title and rejoin the world.
- Wait for the spam. Ouch... nothing happening?
- Run the reload command (or disable the data pack and enable again), the spam will back now.