I moved my domain yesterday from Heroku to DigitalOcean. The process went fine and the website seemed to be working fine on DigitalOcean. Today morning I noticed this error when I tried to access my website
Heroku | No such app There is no app configured at that hostname. Perhaps the app owner has renamed it, or you mistyped the URL.
I checked my domain registrar's (GoDaddy) settings and the nameservers had somehow gotten set back to the default settings. I changed them again to point to DigitalOcean nameservers. After about half an hour I was able to access my website again. But since then the domain at random times keeps on showing the same Heroku error and then after a few minutes starts working again. What could be causing such a bizarre issue? I've cleared my browser cache and cookies.
According to this the DNS seems to have propagated correctly.
The website is hosted using a DigitalOcean droplet on a Ubuntu 14.04 machine.