V1/Jira Integrator : Throws NullReferenceException

Question

The goal is to sync issues from Jira to V1. While Syncing issue using V1 Jira integrator (took release from https://github.com/versionone/VersionOne.Integration.JIRA/releases/tag/9.2.2.0), facing below error :

[INFO] 11-01-2022 18:32:21 [Startup]
[INFO] 11-01-2022 18:33:21 Starting processing...
[INFO] 11-01-2022 18:33:21 Getting issues from JIRA.
[INFO] 11-01-2022 18:33:24 Found 1 defects in JIRA to create in VersionOne.
[INFO] 11-01-2022 18:33:27 Found 1 stories in JIRA to create in VersionOne.
[INFO] 11-01-2022 18:33:27 Checking JIRA issues for duplicates.
[INFO] 11-01-2022 18:33:33 Creating VersionOne Defect for item from JIRA system with identifier RKJTP-3
[ERROR] 11-01-2022 18:33:40 Error during saving workitems: Error writing to output stream
[ERROR] 11-01-2022 18:33:40 Error trying to create Workitem in VersionOne for [/RKJTP-3] Bug - 1 in JIRA:
[ERROR] 11-01-2022 18:33:40 System.NullReferenceException: Object reference not set to an instance of an object.
at VersionOne.ServiceHost.WorkitemServices.WorkitemWriterHostedService.ProcessWorkitem(Object pubobj)
[INFO] 11-01-2022 18:33:47 Creating VersionOne Story for item from JIRA system with identifier RKJTP-4
[ERROR] 11-01-2022 18:33:50 Error during saving workitems: Error writing to output stream
[ERROR] 11-01-2022 18:33:50 Error trying to create Workitem in VersionOne for [/RKJTP-4] Epic - 1 in JIRA:
[ERROR] 11-01-2022 18:33:50 System.NullReferenceException: Object reference not set to an instance of an object.
at VersionOne.ServiceHost.WorkitemServices.WorkitemWriterHostedService.ProcessWorkitem(Object pubobj)
[INFO] 11-01-2022 18:33:50 Checking V1 workitems closed since was closed at 1/1/0001 12:00:00 AM.
[INFO] 11-01-2022 18:33:57 Found 0 workitems closed since 1/1/0001 12:00:00 AM where Source is 'JIRA'.
[INFO] 11-01-2022 18:33:57 Processing finished.
[INFO] 11-01-2022 18:34:21 Starting processing...
[INFO] 11-01-2022 18:34:21 Getting issues from JIRA.
[INFO] 11-01-2022 18:34:23 Found 1 defects in JIRA to create in VersionOne.
[INFO] 11-01-2022 18:34:26 Found 1 stories in JIRA to create in VersionOne.
[INFO] 11-01-2022 18:34:26 Checking JIRA issues for duplicates.
[INFO] 11-01-2022 18:34:34 Creating VersionOne Defect for item from JIRA system with identifier RKJTP-3
[ERROR] 11-01-2022 18:34:38 Error during saving workitems: Error writing to output stream
[ERROR] 11-01-2022 18:34:38 Error trying to create Workitem in VersionOne for [/RKJTP-3] Bug - 1 in JIRA:
[ERROR] 11-01-2022 18:34:38 System.NullReferenceException: Object reference not set to an instance of an object.
at VersionOne.ServiceHost.WorkitemServices.WorkitemWriterHostedService.ProcessWorkitem(Object pubobj)
[INFO] 11-01-2022 18:34:41 Creating VersionOne Story for item from JIRA system with identifier RKJTP-4
[ERROR] 11-01-2022 18:34:45 Error during saving workitems: Error writing to output stream
[ERROR] 11-01-2022 18:34:45 Error trying to create Workitem in VersionOne for [/RKJTP-4] Epic - 1 in JIRA:
[ERROR] 11-01-2022 18:34:45 System.NullReferenceException: Object reference not set to an instance of an object.
at VersionOne.ServiceHost.WorkitemServices.WorkitemWriterHostedService.ProcessWorkitem(Object pubobj)
[INFO] 11-01-2022 18:34:45 Checking V1 workitems closed since was closed at 1/1/0001 12:00:00 AM.
[INFO] 11-01-2022 18:34:49 Found 0 workitems closed since 1/1/0001 12:00:00 AM where Source is 'JIRA'.
[INFO] 11-01-2022 18:34:49 Processing finished.
[INFO] 11-01-2022 18:34:51 [Shutdown]

I could see all the mandatory fields of V1 are there in Jira issue.

Is there a way to compile source code available at : https://github.com/versionone/VersionOne.Integration.JIRA