Hey there. This season, you can refund mods individually rather than reset the whole artifact. However the 'rules' for unlocking higher tier mods remain in place. As you need 3 mods unlocked in tier 1 to be able to buy one from tier 2, if you did this and then bought one in tier 2, you would not then be able to refund one of the 3 tier 1 mods because you need at least 3 to remain unlocked. On each, it will show 'requirements not met'. If you bought a 4th Tier 1 mod, then this will remove the message from the tier 1 mods until you refund one, and it will appear again on the others. The message has nothing to do with the function of the mod, only the ability to refund it.