Looking for an Apartment for One or Two Months

Hi there, I'm/ we're new to the Forum, although occasionally take a peek to see whats going on etc.

Me and my Girlfriend have recently moved to Berlin from London, we've both been really enjoying the city, but we're now in an awkward position of needing s Sublet very soon.
We we're looking forward to moving into a (sublet) place on the 1st of June, but that was cancelled last minute.

Wondering of any tips, or if anyone new anything, maybe a pal has a place etc.

We have been staying in Schöneberg for the last 4 weeks, actually really enjoyed the area, Our next destination was due to be Prenzlauer berg/ Mitte, but we're kind of open minded.
As we sometimes work from home don't necessarily need to be so central, after a trip to the lakes one day we thought it'd be cool to be there, but now due to circumstances we're in a position of not much choice and time.
So any suggestion?
I've been trawling WG_Geschute and the other obvious ones, No one really replies due to high demands i imagine.
Any alternatives?