pfSense, unbound and kolabnow.com

[benfitita 10]

I've noticed I have a problem with resolving kolabnow.com domain from my router. My router has unbound (DNS Resolver) running configured to forward queries to 10.4.0.1. Generally DNS resolution works fine, except for kolabnow.com. I think it's some kind of a problem with my setup, take a look below at this SSH session on router.

Everything's fine when resolving example.com and other domains:

dig @localhost example.com

; <<>> DiG 9.14.12 <<>> @localhost example.com
; (2 servers found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19292
;; flags: qr rd ra ad; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;example.com.			IN	A

;; ANSWER SECTION:
example.com.		86400	IN	A	93.184.216.34

;; Query time: 1471 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Fri Aug 14 12:36:19 CEST 2020
;; MSG SIZE  rcvd: 56

BTW I don't know why it says "2 servers found".

I'm getting SERVFAIL on kolabnow.com. Sometimes it's a timeout.

dig @localhost kolabnow.com

; <<>> DiG 9.14.12 <<>> @localhost kolabnow.com
; (2 servers found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 62834
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;kolabnow.com.			IN	A

;; Query time: 44 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Fri Aug 14 12:41:46 CEST 2020
;; MSG SIZE  rcvd: 41

However, if I query 10.4.0.1 directly, it resolves just fine:

dig @10.4.0.1 kolabnow.com

; <<>> DiG 9.14.12 <<>> @10.4.0.1 kolabnow.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 31597
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;kolabnow.com.			IN	A

;; ANSWER SECTION:
kolabnow.com.		85997	IN	A	95.128.36.41
kolabnow.com.		85997	IN	A	95.128.36.40
kolabnow.com.		85997	IN	A	95.128.36.42

;; Query time: 47 msec
;; SERVER: 10.4.0.1#53(10.4.0.1)
;; WHEN: Fri Aug 14 12:42:33 CEST 2020
;; MSG SIZE  rcvd: 89

Unbound log doesn't reveal any errors, except for "Missing DNSKEY RRset in response to DNSKEY query.". Does it mean kolabnow.com NS is misconfigured? Can I change any unbound settings to workaround this?