Why does a create trigger (that already exists) block all processes in SQL Server 2016 SP3?

I have a situation where the following DDL Statement is rising to the top of my list of processes which I have ordered by the number of processes that each process is blocking (directly or indirectly). Killing this process frees up everything. Before you kill it almost everything backs up behind it (almost, but not quite). CREATE TRIGGER [dbo].[MailReturnCBRHandling] ON dbo.ACC AFTER UPDATE AS Declare @v_Agency_ID varchar(15), @n_SaleID numeric, @n_DebtorID numeric, @n_AccNo numeric, @v_AccStatID varchar(20), @b_AccStatMailReturned bit, @b_AccStatReportsToCBR bit, @b_DebtorMailReturned bit, @b_AccReportsToCBR bit IF UPDATE(Stat_ID) BEGIN DECLARE c_InsertedMailReturnCBR CURSOR FOR SELECT Agency_ID, SaleID , Debtor_ID, AccNo , Stat_ID, IsNull(IsBureau,0) FROM INSERTED OPEN c_InsertedMailReturnCBR FETCH NEXT FROM c_InsertedMailReturnCBR INTO @v_Agency_ID, @n_SaleID, @n_DebtorID, @n_AccNo, @v_AccStatID, @b_AccReportsToCBR WHILE @@FETCH_STATUS = 0 BEGIN -- ************************************************* Get AccStat MailReturned & ReportsToCBR ************************************************* DECLARE c_AccStat CURSOR FOR SELECT MailReturned , ReportsToCBR FROM AccStat WHERE Agency_ID = @v_Agency_ID AND AccStat = @v_AccStatID OPEN c_AccStat FETCH NEXT FROM c_AccStat INTO @b_AccStatMailReturned, @b_AccStatReportsToCBR -- ************************************************* Get Debtor MailReturned ************************************************* DECLARE c_Debtor CURSOR FOR SELECT IsNull(MailReturned,0) FROM Debtor WHERE Agency_ID = @v_Agency_ID AND Debtor_ID = @n_DebtorID OPEN c_Debtor FETCH NEXT FROM c_Debtor INTO @b_DebtorMailReturned -- ************************************************* UPDATE MailReturned ************************************************* IF @b_AccStatMailReturned IS NOT NULL BEGIN IF @b_AccStatMailReturned = 1 AND @b_DebtorMailReturned = 0 BEGIN UPDATE Debtor SET MailReturned = 1 WHERE Debtor_ID = @n_DebtorID INSERT INTO DebtorNote (AGENCY_ID, DEBTOR_ID, NOTE, Priority, StampTime, Supress) VALUES (@v_Agency_ID, @n_DebtorID, 'Auto Generated Note --> Debtor Mail Returned changed from: False To: True','C', GetDate() ,0) END IF @b_AccStatMailReturned = 0 AND @b_DebtorMailReturned = 1 BEGIN UPDATE Debtor SET MailReturned = 0 WHERE Debtor_ID = @n_DebtorID INSERT INTO DebtorNote (AGENCY_ID, DEBTOR_ID, NOTE, Priority, StampTime, Supress) VALUES (@v_Agency_ID, @n_DebtorID, 'Auto Generated Note --> Debtor Mail Returned changed from: True To: False','C', GetDate() ,0) END END -- ************************************************* UPDATE ReportsToCBR ************************************************* IF @b_AccStatReportsToCBR IS NOT NULL BEGIN IF @b_AccStatReportsToCBR = 1 AND @b_AccReportsToCBR = 0 BEGIN UPDATE ACC SET IsBureau = 1 WHERE AccNo = @n_AccNo INSERT INTO DebtorNote (AGENCY_ID, DEBTOR_ID, NOTE, Priority, StampTime, Supress,AccNo,SaleID) VALUES (@v_Agency_ID, @n_DebtorID, 'Auto Generated Note --> Reports To Bureau changed from: False To: True','C', GetDate() , 0, @n_AccNo, @n_SaleID) END IF @b_AccStatReportsToCBR = 0 AND @b_AccReportsToCBR = 1 BEGIN UPDATE ACC SET IsBureau = 0 WHERE AccNo = @n_AccNo INSERT INTO DebtorNote (AGENCY_ID, DEBTOR_ID, NOTE, Priority, StampTime, Supress,AccNo,SaleID) VALUES (@v_Agency_ID, @n_DebtorID, 'Auto Generated Note --> Reports To Bureau changed from: True To: False','C', GetDate() , 0, @n_AccNo, @n_SaleID) END END FETCH NEXT FROM c_InsertedMailReturnCBR INTO @v_Agency_ID, @n_SaleID, @n_DebtorID, @n_AccNo, @v_AccStatID, @b_AccReportsToCBR CLOSE c_Debtor DEALLOCATE c_Debtor CLOSE c_AccStat DEALLOCATE c_AccStat END CLOSE c_InsertedMailReturnCBR DEALLOCATE c_InsertedMailReturnCBR END The trigger is written by the company that provides us with the software that we use to run out business. There is no need to create it because it already exists. It should instantly fail because an object of that name already exists. The vendor provided this software runs the entire application logged in as SA. I have begged my management to make them run all sql under the windows credential of the logged in user but they claim that they have no way to force the software vendor to to that so the SQL process list does not tell me anything about who submitted the create trigger and under what circumstances. We are running SQL Server 2016 SP3. I am wondering: 1) Why would this suspend? Why not just return an error tha t says an object of that name already exists? 2) Given that it has suspended, why do all the other tasks back up behind it? Put another way, what resource is this process holding that the others need. I can't believe that they are all waiting to create or alter triggers or that something that this process needs to change is in a page that everyone else would want. It would be as if this process was able to put a lock on the entire database, but why? This happens about every two weeks. Exact same trigger. I have not yet determined a set of circumstances that trigger it. Thank you.