I cannot resize my lower zone

Can anyone tell why I am unable to resize my cubase lower zone.
I can’t resize it as small or as big as others it’s stuck to a limit.
Do anyone know what should I do ??
I use cubase pro 10.5

Hi and welcome on the forum,

There is a limit of the Lower Zone Size. So maybe, you just reached the limit.

Could you try in the Cubase Safe Start Mode [Disable preferences], please?