Others have said it, but I would also leave a zero if could.
I purchased two tickets to see Florence + the Machine at the 02 in London back in March 2022. The original show was scheduled for 19th November 2022, however, it was cancelled as Florence had broken her foot. It was then rearranged for 28th January 2023.
The e-tickets for the original show were sent from Viagogo to the 02 app. They were visible on the app so that you could gain entry to the 02. However, there were no tickets on the app for the rearranged date.
Therefore, I attended the 02 earlier in the day and checked with the Box Office. They informed me that my allocated tickets were now assigned to other people - basically resold without my knowledge or consent. I therefore had no tickets for the event, and no contact / refund from Viagogo. I travelled from Birmingham to London for this, including a hotel stay.