I had booked a slot for the German national visa at the Bangalore embassy for 15th May 2019, but couldn't attend due to personal problems. I didn't cancel it. When I tried to rebook on 11th June 2019, I got the error saying "the entry should be unique. A different appointment with the same entry was already made". I dropped a mail to email@example.com to remove the details from their database on the same day.
Today I still get the same error. Can somebody tell me how long do they take to remove my details so that I will be able to rebook. I tried approaching the German Embassy customer care, Bangalore but they said "It's not in their scope to know the cancellation".