Well, much like it says: You're trying to get a certificate for the name www.dynhost.ml, but your name's authoritative DNS servers are malfunctioning and not returning a valid answer. That means that Let's Encrypt can't connect to your server in order to validate that you own the name. (And it means that no other users can get to that name either.)
dynhost.ml/DNSKEY: The response (92 bytes) was malformed. (176.9.168.4, 193.254.196.206, UDP_-_EDNS0_512_D_KN, UDP_-_NOEDNS_)
www.dynhost.ml/AAAA: The response (96 bytes) was malformed. (176.9.168.4, 193.254.196.206, UDP_-_NOEDNS_)
www.dynhost.ml/A: The response (64 bytes) was malformed until EDNS was disabled. (176.9.168.4, 193.254.196.206, UDP_-_EDNS0_4096_D_KN)
Your DNS servers are dhost1.ml and dhost2.ml, you'd have to contact whoever administrates your DNS zone on those servers if you're expecting that name to resolve to something.