So on our end, we won’t re-issue the exact same model if a user deletes it. However, we will start training again from scratch the next round, and may re-find that signature and issue a different model for it.
There are quite a few reasons this could be happening, so it’s hard to point to one singular answer as the cause. Considering that it’s been a few weeks, my initial recommendation would be to delete the device and continue with regular usage of your coffee machine so Sense can “try again” with a new model for the device that is hopefully more accurate.