Cannot change master password

[wfaulk-bw]

Every time I try to change my master password with lpass passwd, I get the error "Password change failed":

% lpass passwd
Fetching data...
Re-encrypting [========================================] 993/993
Uploading...
Error: Password change failed.

I enter my existing password in the "full-screen" dialog, and then the new password twice.

This has happened to me multiple times. I always have to use the web UI to change the master password. I'd be happy to provide more information, but I don't know what further information I have access to.