If there are any other London-based eventprofs who commute to work with a monthly travelcard, you can apply for a refund on it here:
https://tfl.gov.uk/fares/refunds-and-replacements/coronavirus
It needs to have seven days left on it, so today/tomorrow is your deadline if you started it at the beginning of the month.
The line is so busy right now I didn’t manage to get through, just FYI. But worth trying to save yourself £100