R&B singer R. Kelly has contracted COVID-19 while awaiting sentencing in a Brooklyn federal jail for his racketeering conviction, his lawyer revealed in a court filing early Tuesday. The singer’s diagnosis has hampered his ability to speak on the phone about his appeal of his conviction, which is due Thursday, said Kelly’s lawyer, Jennifer Bonjean, in asking for a two-week extension. “It is vitally important that Mr. Kelly meaningfully participate in his post-trial defense,” Bonjean wrote in the motion, saying she hoped to communicate with him in an upcoming Zoom call. Bonjean, a New York-base…