What do you mean by registrations? Wake word WAV files?
Generally, the more data, the better. Also try and have 3+ times the number of not wake words vs. wake words. It will also take some time and usage combined with saved wakewords to really improve the model in real world usage in an updated model.
I have maybe 400 wake words and about 2500 not wake words for my model, combined with the google voice commands and public noises datasets. The majority of my not wake words come from false activations. At this point it’s highly accurate for me. I also still record the uttrances, and use the not-wake-words for re-modeling on occasion.