After changing it to :
<a href="<?php wpsight_listing_agent_archive( $listing->ID ); ?>" class="button"><?php _e( 'My Listings', 'wpcasa-sylt' ); ?></a>
it worked.
But maybe there should be domain wpcasa because this string is in core wpcasa plugin too
In Sylt theme in listing-single-agent.php is this code:
<a href="<?php wpsight_listing_agent_archive( $listing->ID ); ?>" class="button"><?php _e( 'My Listings', 'wpsight' ); ?></a>After changing it to :
<a href="<?php wpsight_listing_agent_archive( $listing->ID ); ?>" class="button"><?php _e( 'My Listings', 'wpcasa-sylt' ); ?></a>it worked.But maybe there should be domain wpcasa because this string is in core wpcasa plugin too