"Submit error (500): INTERNAL SERVER ERROR" while changes submission.

Request URL:https://addons.opera.com/api/developer/package-versions/227592-2.0.2/submit_for_moderation/
Request Method:POST
Status Code:500 INTERNAL SERVER ERROR
Remote Address:82.145.215.90:443
Response Headers
view source
Connection:keep-alive
Content-Language:uk
Content-Type:text/html; charset=utf-8
Date:Tue, 15 Nov 2016 14:40:23 GMT
Server:nginx/1.6.2
Transfer-Encoding:chunked
Vary:Cookie, Accept-Language
Request Headers
view source
Accept:application/json; version=1.0
Accept-Encoding:gzip, deflate, br
Accept-Language:uk,ru;q=0.8,en-US;q=0.6,en;q=0.4
Connection:keep-alive
Content-Length:2
Content-Type:application/json;charset=UTF-8