My uncle gave me a Verpflichtungserklärung (declaration of commitment) for my student visa application. It was issued to him on 7th July 2018 with validity starting from 1st September 2018.
I didn't make it for the winter semester, but I hope to make the summer semester that starts in April. That means I will have to go for another visa interview in my country.
Can I still use the same Verpflichtungserklärung to apply for another visa or does it have an expiry date?