500 error while opening merge request gitlab-ce 8.0.3

created a merge request and self assigned it. when i click on the
merge request Not found error appears. the below is messages from the
log

509.Started GET “/Services/ElectionsV3/merge_requests” for 127.0.0.1 at 2015-09-28 09:04:20 +0530

510.Processing by Projects::MergeRequestsController#index as HTML

Parameters: {“namespace_id”=>“Services”, “project_id”=>“ElectionsV3”}

512.Completed 200 OK in 530ms (Views: 284.5ms | ActiveRecord: 92.7ms)

513.Started GET “/Services/ElectionsV3/merge_requests/1” for 127.0.0.1 at 2015-09-28 09:04:21 +0530

514.Processing by Projects::MergeRequestsController#show as HTML

Parameters: {“namespace_id”=>“Services”, “project_id”=>“ElectionsV3”, “id”=>“1”}

516.Started GET “/Services/ElectionsV3.git/info/refs?service=git-upload-pack” for 127.0.0.1 at 2015-09-28 09:04:32 +0530

517.Started GET “/WorkFlow/SocialMedia3.git/info/refs?service=git-upload-pack” for 127.0.0.1 at 2015-09-28 09:04:32 +0530

518.Started GET “/Services/ElectionsV3.git/info/refs?service=git-upload-pack” for 127.0.0.1 at 2015-09-28 09:04:33 +0530

519.Started GET
“/Services/ElectionsV3/notes?target_id=445&target_type=issue&last_fetched_at=1443411258”
for 127.0.0.1 at 2015-09-28 09:04:34 +0530

520.Processing by Projects::NotesController#index as JSON

Parameters: {“target_id”=>“445”, “target_type”=>“issue”,
“last_fetched_at”=>“1443411258”, “namespace_id”=>“Services”,
“project_id”=>“ElectionsV3”}

522.Completed 200 OK in 108ms (Views: 0.4ms | ActiveRecord: 14.6ms)

523.Started GET “/WorkFlow/SocialMedia3.git/info/refs?service=git-upload-pack” for 127.0.0.1 at 2015-09-28 09:04:34 +0530

524.Completed 500 Internal Server Error in 16271ms (ActiveRecord: 92.9ms)

Regards
Sudheesh