Hello, I have a domain registered with Wedos (Czech registrar) and my project is hosted on Vercel. I am currently experiencing an issue with DNS resolution and routing.
Current Behavior:
The website works perfectly when accessed via mobile data. However, when I connect to my local Wi-Fi (using my local ISP’s default DNS), the site fails to load, returning either a 502 Bad Gateway or net::ERR_CERT_AUTHORITY_INVALID error. If I manually switch my DNS servers to Google (8.8.8.8) or Cloudflare (1.1.1.1), the website loads without any issues.
Expected Behavior:
The domain should resolve and load globally without SSL or Gateway errors, regardless of the ISP’s default DNS.
Current DNS Configuration (at Wedos):
| Name | TTL | Type | Data |
|---|---|---|---|
@ |
1800 | A | 216.198.79.1 |
www |
1800 | CNAME | 87d06848933184a6.vercel-dns-017.com. |
Raw DNS Status/Output:
renatyvyklizeni.cz. 3600 IN SOA ns.wedos.net. wedos.wedos.com. 2026042005 3600 1800 1814400 3600
renatyvyklizeni.cz. 1800 IN A 216.198.79.1
renatyvyklizeni.cz. 3600 IN NS ns.wedos.cz.
renatyvyklizeni.cz. 3600 IN NS ns.wedos.eu.
renatyvyklizeni.cz. 3600 IN NS ns.wedos.com.
renatyvyklizeni.cz. 3600 IN NS ns.wedos.net.
www.renatyvyklizeni.cz. 1800 IN CNAME 87d06848933184a6.vercel-dns-017.com.
dig info www.renatyvyklizeni.cz
; <<>> DiG 9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16 <<>> www.renatyvyklizeni.cz
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55915
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;www.renatyvyklizeni.cz. IN A
;; ANSWER SECTION:
www.renatyvyklizeni.cz. 1800 IN CNAME 87d06848933184a6.vercel-dns-017.com.
87d06848933184a6.vercel-dns-017.com. 300 IN A 64.29.17.65
87d06848933184a6.vercel-dns-017.com. 300 IN A 216.198.79.65
;; Query time: 188 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Mon Apr 20 15:55:34 EDT 2026
;; MSG SIZE rcvd: 132
Question: My site works on mobile data and Google DNS, but gives 502 and SSL errors on my home Wi-Fi. What is causing this? Did I set up my DNS incorrectly, do I just need to wait longer for the DNS to update globally, or is there an issue on Vercel’s side with my SSL certificate? I was waiting for propagation 10 days after changings DNS records, there are still errors i mentioned above.