Does leaving supererogatory prayers due to time constraints at work render past prayers unacceptable or necessitate sin?

There is no sin in abandoning supererogatory prayers (Nawafil) as long as the five obligatory prayers have been performed, for, according to the majority of scholars, a Muslim is only obligated to perform the five prayers. Furthermore, abandoning supererogatory prayers now does not invalidate the acceptance of those that were performed in the past. However, a Muslim should not neglect supererogatory prayers, especially the emphasized ones, such as Witr and the regular Sunnah (definition) prayers (Rawatib), for any deficiency in the obligatory prayers will be compensated on the Day of Judgment by the supererogatory ones, and due to the immense rewards associated with them.