"insert into multiple selection"

in Calc attempting routine paste of list of numbers. When do so, get error “insert into multiple selection not possible” Have no idea what this means so cannot solve problem. Help please

Please upload an ODF type sample file here with colorized Source and Target cell ranges for the desired copy-caste.

Or is the Source a some internet content or other foreign “cell range”??

highlighted all rows in destination sheet & then commanded “show rows”. am not sure how rows came to be hidden.

I presume the above is the solution.

Hidden/grouped rows don’t prevent to paste content. Possible the hidden rows were unselected (like when you select with Ctrl).