System finds message to process but does NOT process for some reason

[bvk0118]

2018-04-20 11:06:20,675 [1] INFO Mail2Bug.MainApp [(null)] - --------------- Iteration 1 ---------------
2018-04-20 11:06:20,675 [1] INFO Mail2Bug.Email.EWS.EWSConnectionManger [(null)] - Processing inbox for connection (, , 764706844, True)
2018-04-20 11:06:20,677 [1] INFO Mail2Bug.Email.EWS.RecipientsMailboxManagerRouter [(null)] - Processing inbox for RecipientsMailboxManagerRouter
2018-04-20 11:06:20,870 [1] INFO Mail2Bug.Email.EWS.RecipientsMailboxManagerRouter [(null)] - Adding message to client queue: Client ID 100; subject: Test 27 - 52
2018-04-20 11:06:20,870 [1] INFO Mail2Bug.Email.EWS.RecipientsMailboxManagerRouter [(null)] - Finished processing inbox for RecipientsMailboxManagerRouter
2018-04-20 11:06:20,870 [4] INFO Mail2Bug.Mail2BugEngine [(null)] - Initalizing MailboxManager
2018-04-20 11:06:20,871 [4] INFO Mail2Bug.Helpers.DPAPIHelper [(null)] - Reading encrypted data from file .\Resources\password.bin
2018-04-20 11:06:20,872 [4] INFO Mail2Bug.Email.EWS.EWSConnectionManger [(null)] - FolderMailboxManager for (, , 764706844, True) already exists - retrieving from cache
2018-04-20 11:06:20,968 [4] INFO Mail2Bug.Mail2BugEngine [(null)] - Initializing WorkItemManager
2018-04-20 11:06:20,969 [4] INFO Mail2Bug.Mail2BugEngine [(null)] - Running for config instance ''