SQL Time out Exception

Question

some time I am getting this error in my splunk server, could you please help me, why I am getting this error.

Execution Timeout Expired. The timeout period elapsed prior to completion of the operation or the server is not responding

in config file we already have <add key="SqlCommandTimeout" value="120" /> But still we are getting that error in Production, please help me what could be the cause for this.

This is the stack trace info -

<error Source="System.Transactions" TargetSite="Void EndCommit(System.Transactions.InternalTransaction)">The transaction is in doubt.</error>

<error Source=".Net SqlClient Data Provider" TargetSite="Void OnError(System.Data.SqlClient.SqlException, Boolean, System.Action`1[System.Action])">Execution Timeout Expired. The timeout period elapsed prior to completion of the operation or the server is not responding.</error>

<error Source="" TargetSite="">The wait operation timed out</error>

<stack> at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)</stack>

<stack> at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)</stack>

c# .net