Hi there.
Many thanks for your reply. For the desktop version your solution works ok, because the sticky starts with the main header row and by hiding the header bottom row when sticky it’s ok, but now on mobile version when i hide the main header and the sticky starts it gives like a small jump because its changing the display mode to none for that row and that is not good as it looks like a bug, it’s not fluid.
Is there any way you can help me to sort this out?

Many thanks