@Pranithakat Have you added secureCookie as true varible in Experience Cloud ID service extension ? If not than can you try adding that ? I am assuming that you have only ticked the secure cookie checkbox in Analytics extension.
@Pranithakat This would work only for https website, Is your website on https protocol ?
The SecureCookie configuration will not work on unsecured domains and could result in you not receiving the MID values for visits that use an unsecured protocol. The secureCookie configuration should be set to true only when you are sure that all pages and sub-domains are using a secure protocol at all times.