The Invalid Record List Indexer error is issued in the following situations:
'Record List' variable indexer must be an 'Integer': you are indexing your List by a number that is not an integer.
Check the data type of your index because the  operator expects an integer value.
Only 'Record List' elements can be indexed: you are indexing an element that is not a List.
Change the element data type because the  operator can only be used with Lists.
Clicking the symbol will take you directly to the element where this situation was detected.
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