The issue started a few hours ago. Here is the dig response:
dig ocsp.int-x3.letsencrypt.org
; <<>> DiG 9.11.3-1ubuntu1.18-Ubuntu <<>> ocsp.int-x3.letsencrypt.org
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 32507
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;ocsp.int-x3.letsencrypt.org. IN A
;; Query time: 3 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Mon Mar 06 19:39:16 GMT 2023
;; MSG SIZE rcvd: 56