Jira integration page is not opening in Gitlab. Integration has stopped working

When clicking on JIra under integration tab(settings), Jira integration page is not opening & throwing 500 error.

While logged in, try to access [https://xxxx/project-path/-/settings/integrations/jira

It was opening previously. Recently have upgraded GitLab to this version.
Current GitLab version 12.8.5. previous version was:12.6.4

Error getting in production.log::

Processing by Projects::JobsController#show as JSON
Parameters: {“namespace_id”=>“Pensions”, “project_id”=>“deployments”, “id”=>“232034”}
Started GET “/Linux/rhel7applications/-/services/jira/edit” for at 2020-04-09 09:29:13 +0200
Processing by Projects::ServicesController#edit as HTML
Parameters: {“namespace_id”=>“ISDLinux”, “project_id”=>“rhel7-applications”, “id”=>“jira”}
Completed 500 Internal Server Error in 57ms (ActiveRecord: 8.7ms | Elasticsearch: 0.0ms | Allocations: 20802)

ActionView::Template::Error (must specify an iv):
1: - name = field[:name]
2: - title = field[:title] || name.humanize
3: - value = @service.send(name)

Can anyone please help?

You seem to be affected by issue https://gitlab.com/gitlab-org/gitlab/issues/198490

First run:

sudo gitlab-rake db:migrate:status

and make sure all migrations are up.

If they are, run the following two commands:

sudo gitlab-rake db:migrate:redo VERSION=20200123155929
sudo gitlab-rake db:migrate:redo VERSION=20200127090233

and then check if the integration page opens without a 500 error.