Covid-19 has caused many conferences to cancel, postpone, or revise their format. I've updated the 2020-2021 Upcoming Accessibility and UI/UX Conferences post at https://accessible-techcomm.org/2020-2021-upcoming-accessibility-and-ui-ux-conferences/ to show the revised dates and locations.
Check the rest of the scheduled conferences through this year and 2021. Some have been postponed for a year and some have moved to the Fall / Winter of this year. For example, Funka is usually held in Sweden in April. It was postponed to the end of November and you now have your chance to see Sweden in Winter.
If you've already made reservations for the conference, check with the conference website to see what their plans are for reimbursing you or applying payments to the 2021 or 2022 conference. They will also have information for cancelling hotel and travel reservations.
If you also attend TechComm conferences, check the revised dates for those at https://events.stcwdc.org/2020-2021-upcoming-techcomm-conferences/.
Check back again in a few months in case some of the ones who postponed to the Fall / Winter have changed to virtual or moved to 2021 or 2022.