Not sure what you mean by “Is is mandatory to have same name of Loops and segments in document type and Connectors?”.
When you loop through elements you need to point the list elements that you are going to loop through, both input and output lists must be pointed to the Repeat, or Loop. If your output list already exists and it has elements in it only then you need to use appendToList service. 1 to 1 list mappings don’t require AppendService. When you map your input and output lists to loop or repeat, you must see the array indicator disappear in the loop section hence you will end up with elements instead of lists in the loop. If you still see the lists in the pipeline that means you didn’t map it properly. Loop services has to have correct path to the list, you can just copy and paste it from any element.
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