After change in NS to Cloudflare site/app not accessible at some locations

[vershak]

1. We were doing activity for migrating [https://www.glossaread.com] DNS Server to AWS Route53.
2. We had changed the NS record of domain which was on route 53 on our domain name provider crazy domain.
   We had to wait for 4 hours for NS record to get reflect globally as per crazy domain SLA.
3. After 4 hours we checked and website was not accessible for most of the users so we reverted back to old Cloudflare NS record. Its been almost 24 hours now but Users are still facing the error to accessing the website/app, NS records are already pointed to Cloudflare which i can see in the DNS record.
   We did not modified any server side settings during this activity.

Need your urgent support to resolve this issue as users are facing problem to accessing the website and at some places only the mobile app.
Things we already did , but did not find any luck

1. Clears the browser cache
2. Flushed the Local DNS

[sdayman]

With frequent NS changes, it takes time for DNS to stabilize. It can take up to 48 hours for a NS change to fully propagate, so it’s best to switch and let it catch up.

As of now, a global test shows the site reachable from all functioning test locations.

[vershak]

Thank you for your response. Unfortunately the support team very clearly responds back saying TTL is 2-4 hours, depending on DNS queue.