Jpm sign causes "Error: request URL was not specified"

Hi,

When I tried to sign my xpi package with “jpn sign” command,
it caused “Error: request URL was not specified” and
"Error: Validation took too long to complete; last status: [null]".
(The detail output follows.)

I got the same error on both Windows and Linux.

What’s wrong with this, and how can I fix it?

JPM [info] Signing XPI: @url2qr-0.0.4.xpi
Potentially unhandled rejection [1] Error: request URL was not specified
    at Client.configureRequest (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\lib\amo-client.js:383:11)
    at C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\lib\amo-client.js:421:24
    at init (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\node_modules\when\lib\makePromise.js:39:5)
    at new Promise (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\node_modules\when\lib\makePromise.js:27:53)
    at Function.promise (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\node_modules\when\when.js:98:10)
    at Client.request (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\lib\amo-client.js:420:15)
    at Client.get (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\lib\amo-client.js:308:23)
    at checkSignedStatus (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\lib\amo-client.js:127:12)
    at C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\lib\amo-client.js:179:5
    at init (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\node_modules\when\lib\makePromise.js:39:5)
Validating add-on [                                          .                 ]
JPM [error] FAIL
Error: Validation took too long to complete; last status: [null]
    at null._onTimeout (C:\Users\snaga\AppData\Roaming\npm\node_modules\jpm\lib\
amo-client.js:184:14)
    at Timer.listOnTimeout (timers.js:92:15)

Did you check on AMO if the file was signed?