can't change password

[ginuerzh]

I use ejabberd 16.03 on ubuntu 14.04

my mod_restful config:

listen:

port: 5289
module: ejabberd_http
request_handlers:
    "/api": mod_restful

mod_restful: api:

    path: ["admin"]
    module: mod_restful_admin
    params:
      key: "admin"
      allowed_commands: [register, unregister]
  -
    path: ["register"]
    module: mod_restful_register
    params:
      key: "admin"

First I register an account, that's ok. but when I want to change the password:

http://localhost:5289/api/register/change_password

the log tell me: [error] <0.18174.0> Processing throwed error undef trace: [{ejabberd_auth,check_password,[<<"abcdefg">>,<<"localhost">>,<<"123456">>],[]},{mod_restful_register,post_change_password,1,[{file,"src/mod_restful_register.erl"},{line,124}]},{mod_restful,handle_rest_request,5,[{file,"src/mod_restful.erl"},{line,193}]},{mod_restful,process,2,[{file,"src/mod_restful.erl"},{line,161}]},{ejabberd_http,process,5,[{file,"src/ejabberd_http.erl"},{line,363}]},{ejabberd_http,process_request,1,[{file,"src/ejabberd_http.erl"},{line,451}]},{ejabberd_http,process_header,2,[{file,"src/ejabberd_http.erl"},{line,291}]},{ejabberd_http,parse_headers,1,[{file,"src/ejabberd_http.erl"},{line,211}]}]