Is one who sometimes prays the congregational prayer at home, due to illness or oversleeping, sinful?

Congregational prayer is obligatory for able-bodied men, whether residents or travelers. Sleep is an excuse for missing congregational prayer if it was not due to negligence. However, whoever stays up late without need and abandons the means that help one wake up is sinful. Therefore, there is no blame on you for missing the congregational Dhuhr prayer if it was due to an excuse; otherwise, repentance is obligatory, and you must perform it with the congregation in the future.