The MSDTC transaction manager was unable to pull the transaction

Hello,

We have BizTalk Server and SQL Server database running on different server. Past a month we are getting below issue ..

We checked on firewall, the ports are open and DTC is configured correctly. This was running before.

Pls help

Cannot open database BizTalkMgmtDb on server doman\instance.Verify that you have the required security permissions and that communication between Distributed Transaction Coordinator services on the machines involved is not prevented by current DTC security, firewall or authentication settings. (Microsoft.BizTalk.Administration.SnapIn)

For help, click: http://go.microsoft.com/fwlink/?LinkId=47400&ProdName=Microsoft+BizTalk+Server+2016&ProdVer=3.12.774.0&EvtSrc=Microsoft.BizTalk.ApplicationDeployment&EvtID=ConnectDBFailed

ADDITIONAL INFORMATION:

Exception of type 'System.EnterpriseServices.TransactionProxyException' was thrown. (Microsoft.BizTalk.ExplorerOM)

Communication with the underlying transaction manager has failed. (System.Transactions)

The MSDTC transaction manager was unable to pull the transaction from the source transaction manager due to communication problems. Possible causes are: a firewall is present and it doesn't have an exception for the MSDTC process, the two machines cannot find each other by their NetBIOS names, or the support for network transactions is not enabled for one of the two transaction managers. (Exception from HRESULT: 0x8004D02B) (System.Transactions)