DNS Servers need some time for the migration. Normally clients are also caching certain DNS requests.
Waiting up to 12 hours should resolve the issue.

@mobidi

If the DNS for your domain was already set to another provider, it’s possible for propagation to take as long as 24-48h. In most cases, it’s as quick as few minutes to an hour, though I’ve seen cases that extend out longer.

If you’ve already closed out your previous account with the previous provider, there could be a period of time where users won’t be able to connect due to propagation, so that very well could be the case.

To make sure it’s not an issue on the server, I’d recommend checking your error logs to see if anything pops up such as errors relating to connections, file errors, etc.