What is the ruling of the Shari'ah concerning one who continuously laughs in their prayer involuntarily, and is it permissible for them to pray alone?

One should strive to achieve humility and devotion (khushu') in prayer by various means, such as lowering the gaze, occupying one's thoughts with communion with God, and envisioning oneself standing before Him. Prayer is about humility, modesty, and glorification of God. The worshipper must be diligent in their prayers and not allow Satan to distract them with his whisperings. Deliberate laughter during prayer is not permissible, nor is it an excuse for failing to join the congregational prayer.