Madonna appeared as the interval act at the Eurovision Song Contest in May 2019; she performed "Like a Prayer", and then "Future" with rapper Quavo. The Madame X Tour, an all-theatre tour in select cities across North America and Europe, began on September 17, 2019. In addition to much smaller venues compared to her previous tours, Madonna implemented a no-phone policy in order to maximize the intimacy of the concert. According to "Pollstar", the tour earned $51.4 million in ticket sales. That December, she started dating Ahlamalik Williams, a dancer who began accompanying her on the Rebel Heart Tour in 2015. However, the Madame X Tour faced several cancellations due to her recurring knee injury, and eventually ended abruptly on March 8, 2020, three days before its planned final date, after the French government banned gatherings of more than 1,000 people due to COVID-19 pandemic. Madonna later admitted that she tested positive for coronavirus antibodies, and donated $1 million to the Bill &amp; Melinda Gates Foundation to help fund research creating a new vaccine.