3150934 - Cannot connect to direct connect serivce: Error 11001 WSA HOST_NOT_FOUND - MFC

Error when trying to connect direct connect service via ISQL:

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TCPIP Network Error: { [NOTCONNECTED] Lost connection to database, ,

Request(Connect),SubFunc(Failed), SYBTCP RetCode(1) Description(SYBTCP_FAIL),
TCP API RetCode (11001) Description(WSA HOST_NOT_FOUND) } <HostName=xxxx>,
<PortNumber=1111>, <Region Name=cics01>, <TPName=yyy>
Msg 30000, Level 16, State 0:
Server 'DDDDD':
Login failure. <SMR>
CT-LIBRARY error:
ct_connect(): protocol specific layer: external error: The attempt to connect to the server failed.

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In the log:

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LogNotice 02/14/2022 14:56:10.672 DAIU1 7 sa isql NETWORK ERROR: SYBTCP ERROR INFO:, Request(Connect),SubFunc(Failed), Request(Connect),SubFunc(Failed), SYBTCP RetCode(1) Description(SYBTCP_FAIL), TCP API RetCode (11001) Description(WSA HOST_NOT_FOUND) errmsg[Win NT system call sybtcp_connect: gethostbyname, error num 11001, tranaction YYYY, region name CICS01, host name XXXX, port num 1111 ]
LogClientMessages 02/14/2022 14:56:10.678 DAIU1 7 sa isql Error: 30261 Severity: 10 TCPIP Network Error: { [NOTCONNECTED] Lost connection to database, , Request(Connect),SubFunc(Failed), SYBTCP RetCode(1) Description(SYBTCP_FAIL), TCP API RetCode (11001) Description(WSA HOST_NOT_FOUND) } <HostName=xxxx>, <PortNumber=1111>, <Region Name=cics01>, <TPName=yyyy>

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Mainframe Connect DirectConnect 15.0.1

MFC direct connect Mainframe Connect DirectConnect db2.cfg  ConnectionSpec1 DNS problem firewall WSA HOST_NOT_FOUND error num 11001 Error 30261 TCPIP Network Error: { [NOTCONNECTED] Lost connection to database SYBTCP_FAIL 30000 login failure gethostbyname , KBA , BC-SYB-MFC , Mainframe Connect (MFC) , Problem