layout issue

I am using the 2 panes 1 above the other layout. I just moved the top window up and now its stuck and i cannot reset the window (screenshot)
I have tried resetting layout but it has not changed and I cannot grab the line between the 2 windows anymore.
any help would be greatly appreciated,
I am using 4.18.3 engine

Hello,

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https://epicsupport.force.com/unrealengine/s/

Thanks