User removing their key cause authorized_keys file is cleared

We upgrade to gitlab7.9.1 and gitlab-shell 2.6.0,

but when any user “Remove” their own ssh key from web GUI, the authorized_keys file on the server will be empty. (It is a sure thing that this is not caused by gitlab-keys clear since no line in the authorized_keys file after that).

We dont’ know whether it is a bug or we configure something wrong, please help.

sorry, forget about it. The folder capacity is full, that causes the problem. :*(