DNS Propagation of client's domain is not successful

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DNS propagation (the process of updating domain information on the internet’s Domain Name System servers) take longer depending on Time to Live (amount of time a DNS server caches a DNS record before it needs to be updated) of the DNS record, the record type (NS, CNAME. SPF, TXT, MX, A, AAAA), the DNS cache, and network conditions of your infrastructure or the decentralized system of Domain Name System servers.

DNS propagation takes 24hrs to 48 hours, however for some providers it can take up to 72 hours mainly because of Time to Live of specific domain providers.

Therefore its safe to say if you have a lower Time to Live (factor you can control) then you have shaved propagation time. However, the rest depends on all the aforementioned factors.

A more quicker way is to use cloudflare as your dns manager. Cloudflare DNS | Authoritative and Secondary DNS