Nginx: Error: unsupported certificate purpose

2021/10/03 03:12:19 [info] 1880368#1880368: *51222 client SSL certificate verify error: (26:unsupported certificate purpose) while reading client request headers, client: 10.0.0.10, server: specialistoff.net, request: "GET / HTTP/1.1", host: "specialistoff.net"