Busybox 1.30.1-6 does not work correctly

[h4de5]

nslookup easylist-downloads.adblockplus.org
Server:         127.0.0.1
Address:        127.0.0.1#53

*** Can't find easylist-downloads.adblockplus.org: No answer
Name:      easylist-downloads.adblockplus.org
Address 1: 2a01:4f8:200:11e9::2
Address 2: 2a01:4f8:201:71e5::2
Address 3: 2a01:4f8:200:2175::2
Address 4: 2a01:4f8:171:1945::2

as soon as I tried the url in my browsers (instead of trying it directly on the router cli) I get this:

nslookup easylist-downloads.adblockplus.org
Server:         127.0.0.1
Address:        127.0.0.1#53

Name:      easylist-downloads.adblockplus.org
Address 1: 176.9.139.5
Address 2: 148.251.12.230
Address 3: 178.63.13.4
Address 4: 195.201.59.244
Address 5: 88.99.186.151
Address 6: 144.76.137.234
Address 7: 144.76.219.20
Address 8: 144.76.137.80
Address 9: 144.76.153.101
Address 10: 213.239.192.206
Address 11: 176.9.127.15
Address 12: 176.9.26.105
Address 13: 2a01:4f8:160:130c::2
Address 14: 2a01:4f8:141:132c::2
Address 15: 2a01:4f8:202:81c8::2
Address 16: 2a01:4f8:222:1982::2

and after like 10min its back to "No answer".

so its definitely my weird dns setup.
(which is like: dns requests are forwarded to the router port 53, where adblock uses dnsmasq as backend, which forwards all non-local addresses to port 5453 where stubby is waiting to us DOT to eventually resolve it)
so not an adblock issue. seems like a local dns request is not forwarded correctly. I'll try to figure out whats wrong - and update it here. Thank you again for helping me so far and putting me on the right track!

[vgaetera]

Try to stick with a single major DoT provider like Google or Cloudflare.
Remove IPv6 resolvers if your ISP doesn't provide IPv6 connectivity.
Reinstall/upgrade the packages:

opkg update; opkg --force-reinstall install ca-certificates stubby

[h4de5]

I am using 9quad. ipv6 is disabled everywhere.

Do I need both? ca-bundle and ca-certificates? I switched now to cloudflare temporarily - but I keep getting the same result. If i query stubby directly on port 5453 I am not getting any answer for that domain even if get a valid answer on port 53 .. but do get one for domains like www.google.org - or others I have certainly not used..

/edit: nslookup and dig show different results.. suns getting real low ..

root@charon:~# dig easylist-downloads.adblockplus.org @127.0.0.1 -p 5453

; <<>> DiG 9.16.3 <<>> easylist-downloads.adblockplus.org @127.0.0.1 -p 5453
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 60487
;; flags: qr rd ra; QUERY: 1, ANSWER: 12, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;easylist-downloads.adblockplus.org. IN A

;; ANSWER SECTION:
easylist-downloads.adblockplus.org. 23 IN A     136.243.154.20
easylist-downloads.adblockplus.org. 23 IN A     178.63.13.4
easylist-downloads.adblockplus.org. 23 IN A     178.63.70.146
easylist-downloads.adblockplus.org. 23 IN A     95.216.27.32
easylist-downloads.adblockplus.org. 23 IN A     144.76.116.39
easylist-downloads.adblockplus.org. 23 IN A     144.76.153.101
easylist-downloads.adblockplus.org. 23 IN A     136.243.22.80
easylist-downloads.adblockplus.org. 23 IN A     213.239.192.206
easylist-downloads.adblockplus.org. 23 IN A     195.201.59.236
easylist-downloads.adblockplus.org. 23 IN A     195.201.59.237
easylist-downloads.adblockplus.org. 23 IN A     178.63.50.140
easylist-downloads.adblockplus.org. 23 IN A     144.76.100.145

;; Query time: 9 msec
;; SERVER: 127.0.0.1#5453(127.0.0.1)
;; WHEN: Mon Aug 24 21:41:08 CEST 2020
;; MSG SIZE  rcvd: 663

root@charon:~# nslookup -p 5453 easylist-downloads.adblockplus.org 127.0.0.1
Server:         127.0.0.1
Address:        127.0.0.1#5453

*** Can't find easylist-downloads.adblockplus.org: No answer
Name:      easylist-downloads.adblockplus.org
Address 1: 2a01:4f8:140:30e7::2
Address 2: 2a01:4f8:120:724c::2
Address 3: 2a01:4f9:2a:1b61::2
Address 4: 2a01:4f8:13b:64e::2