I am loosing the values on record whenever I am trying to pass the map value to the list, and also it is not been updated it. Herewith I have attached the debug code:
USER_DEBUG|[403]|DEBUG|posUpdate record -->Position__c:{Affiliation_Final__c=a03N0000000mQEKIA2, Position_Type__c=Warden, Id=a07N0000000iA6lIAE}
11:21:17.825 (825365000)|SYSTEM_METHOD_EXIT|[403]|System.debug(ANY)
11:21:17.825 (825386000)|SYSTEM_METHOD_ENTRY|[404]|String.valueOf(Object)
11:21:17.825 (825402000)|SYSTEM_METHOD_EXIT|[404]|String.valueOf(Object)
11:21:17.825 (825413000)|SYSTEM_METHOD_ENTRY|[404]|System.debug(ANY)
11:21:17.825 (825418000)|USER_DEBUG|[404]|DEBUG|id ->null
11:21:17.825 (825422000)|SYSTEM_METHOD_EXIT|[404]|System.debug(ANY)
11:21:17.825 (825439000)|SYSTEM_METHOD_ENTRY|[405]|String.valueOf(Object)
11:21:17.825 (825453000)|SYSTEM_METHOD_EXIT|[405]|String.valueOf(Object)
11:21:17.825 (825464000)|SYSTEM_METHOD_ENTRY|[405]|System.debug(ANY)
11:21:17.825 (825468000)|USER_DEBUG|[405]|DEBUG|Affiliation_Final__c ->null
11:21:17.825 (825472000)|SYSTEM_METHOD_EXIT|[405]|System.debug(ANY)
11:21:17.825 (825516000)|DML_BEGIN|[406]|Op:Update|Type:Position__c|Rows:2
11:21:17.826 (826821000)|DML_END|[406]
11:21:17.826 (826971000)|EXCEPTION_THROWN|[406]|System.DmlException: Update failed. First exception on row 0; first error: MISSING_ARGUMENT, Id not specified