Overprint or signature on Zwickau note? [Resolvido]

Hello,

I have this note from Zwickau In my collection, but my example has what appears to be a red signature or possibly an overprint added at the top, which I am unable to read it due to the font. 

Has anyone seen something similar to this that could provide some information?

It reads ‘ungültig’ - void in addition to the holes.

Thank you for the help. Exactly the information I was looking for. Glad someone could read it since I couldn’t find other examples elsewhere to compare to.