Add extra shortcodes in sms body

functions.php

<?php

//Add new shortcodes
add_filter( 'sat_sms_get_order_shortcodes', function( $codes ) {
     $codes[] = '[order_pdf_voucher]';
     return $codes;
} );

// For displaying your shortcoders in backend settings
add_filter( 'sat_sms_shortcode_insert_description', function( $content ) {
     return $content . ' For PDF voucher add [order_pdf_voucher]';
} );

// For modifying the sms body with including your shortcoders.
add_filter( 'sat_sms_pharse_body', function( $body, $data ) {
    $vaoucher_code = get_post_meta( $data['order_id'], '_order_key', true );
    return str_replace( '[order_pdf_voucher_code]', $vaoucher_code, $body );
},10, 2);