The Ricoh Theta Z1 camera is now discontinued and a new model to be announced by the end of March:
The RICOH THETA Z1 has been sold out due to its popularity.
February 25, 2021
Thank you for your continued patronage of THETA.
We are pleased to inform you that the RICOH THETA Z1 has been sold out due to its popularity.This is because of the compliance with new laws and regulations in Japan and the difficulty in obtaining some of the parts used.
Currently, we are urgently preparing to deliver products that comply with laws and regulations as soon as possible, and we believe that we will be able to inform you by the end of March.We apologize for the inconvenience and thank you for your understanding. (source)