Thanks Brajesh

This worked

 add_action( 'bp_activity_entry_meta', function () {
    global $activities_template;

    // Check if the current activity's user is the logged in user
    if ( bp_get_activity_user_id() === get_current_user_id() ) {
        // Check if the activity type is 'new_classified'
        if ( 'new_classified' === $activities_template->activity->type ) {
            echo '<a href="https://www.nigerpress.com/manage-listings/" class="advert-edit-link">Manage / Edit Ad</a>';
        }
    }
} );
 

What about this

 function open_external_links_in_new_tab_bp_activity( $query_string, $object ) {
  if ( $object != 'activity' ) {
    return $query_string;
  }
  ?>
  <script type="text/javascript">
  var links = document.getElementsByTagName("a");
  for (var i = 0; i < links.length; i++) {
    var link = links[i];
    if (link.hostname != window.location.hostname) {
      link.target = "_blank";
    }
  }
  </script>
  <?php
  return $query_string;
}
add_filter( 'bp_ajax_querystring', 'open_external_links_in_new_tab_bp_activity', 10, 2 ); 

or maybe using a profile group id 4323 to identify CONTACT DETAILS profile group

 function bp_add_contact_button() {

	// Check if the current user is logged in
	if ( !is_user_logged_in() ) {
		return;
	}

	// Get the current user's ID
	$user_id = bp_displayed_user_id();

	// Get the field data for the "Contact Information" profile group
	$field_data = bp_get_profile_group_field_data( array( 'user_id' => $user_id, 'group_id' => 4323 ) );

	// Check if the "Contact Information" profile group has at least one field updated
	if ( !empty( $field_data ) ) {
		$contact_user_button_args = array(
			'id'                => 'contact_user',
			'component'         => 'members',
			'must_be_logged_in' => true,
			'block_self'        => true,
			'link_class'        => 'contact-user',
			'link_href'         => esc_url( bp_displayed_user_domain() . bp_get_profile_slug() . '/#item-body' ),
			'link_text'         => __( 'Contact Me' ),
		);
		echo bp_get_button( $contact_user_button_args );
	}
}
add_action( 'bp_member_header_actions', 'bp_add_contact_button' ); 

Hi I just noticed the the link also appears in the activities of other members instead of only displaying in the activity of the current logged in user