Formatting lost when pasting greater than 35 rows

I usually want to paste pivots without the underlying data, so I paste from the clipboard as this does a nice job of preserving the formatting. Now I noticed, seemingly randomly, that sometimes the formatting was lost and just the raw text was pasted. I persevered to investigate why some tables pasted ok and others were just text and eventually discovered that any copied data that consists of 36 or more rows looses its formatting when pasted. I can get around this by cutting and pasting the pivots by cutting 35 rows at a time and pasting them separately but thought theres got to be a better solution.

I appreciate your interest here MarvinP and you are right to ask these questions to be able to have any chance of advising and solving this issue. Your questions got me thinking about this being a memory related issue as when I created a new test file, I discovered a different scenario and the statement I made about the formatting being lost above 36 lines was not repeatable. However the issue is still repeatable and I will explain and also try and answer your questions.
Environment: Lenovo Thinkpad X1 Carbon running Windows10 64bit 8gb, Excel 365, no keyboard applications or enhancements running, using Ctrl-C to copy and selecting from the clipboard side panel.no other software is running.
Recreating this issue is repeatable, I too the data attached and made a pivot large enough to play with enough rows and columns (A1:W147). (I tried to attach file Pivot format lost test.xls). I select all the cells by dragging around them and Ctrl-C, then select new sheet and open the clipboard sidebar (using the small corner arrow in the top toolbar).
My first attempt with this newly created file yielded success - the data was pasted with all the formatting preserved - then I did the process again and the formatting was lost - as if the memory couldn't cope with another frame of copied data.
So how can I check whats going on with the memory available to the clipboard, because I think this is where the issue lays.

Great explanation MarvinP - I'm sure under the skin Excel is dealing with a lot of information and the formatting aspect is a 'nice to have preserved' but ultimately the cell data is the important thing for it to get right. I won't bore every reader with pursuing this further but for interest I went back to the file, copied the whole pivot on the PIV worksheet, pasted to a new worksheet (from the clipboard sidebar)and saw it successfully paste including the formatting (the nice blue title, the bold and indented text exactly reproducing the pivot table look). Then I immediately repeated it - copied the pivot, paste into new worksheet and found only plain text was pasted. (I attached the result)
I conclude that there is a memory issue at play. Even clearing the clipboard or even restarting excel wouldn't reset the situation. I wonder if the clipboard memory can be somehow increased.