Sendbird apparently does not respect candidates. They have a bad habit of ghosting candidates and not replying to polite followup emails. We all understand that there could be changes, such as hiring freezes, the worse thing Sendbird did is to make it feel like they do not want the candidate - candidates arent stupid, we can read the signs that Sendbird has frozen hiring. So pls just say it for what it is rather than keep silent and ghost a candidate who has been through the entire process.
This behaviour reflects the attitude of the company's management and culture. Join Sendbird if you can take that kind of disregard of respect for a person.