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My guess is that your cell A1 is EMPTY, hence Google Sheets thinks that row is empty.
Simply insert something into cell A1, so the new rows will be added below it.
Hope this helps! Let me know if there are any further questions or issues.
— @samliew
P.S.: Did you know, the concepts of about 70% of questions asked on this forum are already covered in the Make Academy. Investing some effort into it will save you lots of time and frustration using Make later!