I don’t know your specific focus area but what I have seen some non-profits do who used to rely on a large fundraiser is repackage their offerings and distribute them to a broader group of people that includes potential donors, etc. . With that offering you could then ask people who have the means to donate to help continue your outreach, etc. .
There are also software platforms like Galabid.co.nz that allow you do online silent auctions, raffles, etc. . I have not used them personally but my involvement with a non-profit in the US we would run in person and digital auctions as we realized not everyone could make our fundraiser.
Finally, and again not sure what your annual fundraiser event was, but if generated a list of attendees I would not hesitate to reach out to them to let them know how you are going during this time, how you are providing services for the community, and where your shortfall is and asking them if they be willing to donate at this time.
Hope the above helps.