Welcome to the Atlassian developer community, @Harshitha.
I can deduce that you are using Jira Server or Data Center, not Jira Cloud, because there is an outstanding feature request for custom domains for Jira Cloud. It’s important to pay attention to the difference because the REST API endpoints and authentication mechanisms are different enough to cause problems.
With that information, you should be able to continue to use basic auth. Per our community suggestions, additional details about the request and any error messages you receive would help everyone provide you better advice.
In addition to simple username/password, recent versions of Jira support Personal Access Tokens. These offer better security (because they can be revoked without disrupting user login) and are easier (because they are simply passed as a Bearer token in the Authorization header.