Hi @Suteja Kanuri​ 

My pipeline is running DBR 12.1.

Is it because we're trying to do a merge with tables that are streaming live tables?

In case I'm missing something, here is my pipeline config:

{
    "id": "**********************************",
    "clusters": [
        {
            "label": "default",
            "autoscale": {
                "min_workers": 1,
                "max_workers": 2,
                "mode": "ENHANCED"
            }
        }
    ],
    "development": true,
    "continuous": true,
    "channel": "PREVIEW",
    "edition": "ADVANCED",
    "photon": false,
    "libraries": [
        {
            "notebook": {
                "path": "/Repos/************/************/DLT/attendance/regPeriods/dlt_reg_periods_python"
            }
        },
        .
        .
        .
       .
 
        }
    ],
    "name": "CABS-Streaming-Processes_Dev",
    "storage": "dbfs:/pipelines/************************",
    "configuration": {
        "pipelines.enableTrackHistory": "true",
        "spark.databricks.secureVariableSubstitute.enabled": "false",
        "spark.databaseUser": "{{secrets/***********/**************}}",
        "spark.databasePassword": "{{secrets/**********/*******************}}",
        "spark.databricks.delta.schema.autoMerge.enabled": "true"
    },
    "target": "CABS_dataProcessing_Dev"
}