For souls who wasted time and opportunities for merit
From the Novena for the Holy Souls in Purgatory
Sacred Scripture: Ephesians 5:15-16
Meditation for Day 2
The second sorrow of the holy souls, as St. Alphonsus reflects, is the painful awareness of opportunities lost in life — moments that could have been spent in love of God and neighbor but were not. St. Paul urges the living: Look carefully then how you walk, not as unwise but as wise, making the best use of the time (Eph 5:15-16). The souls in Purgatory cannot now earn new merits; only we, through our prayers and good works, can hasten their purification. This day we pray especially for those who died with much left undone in their service of God, and we ask for the grace ourselves to use our remaining days faithfully.
Daily Novena Prayer (recited every day)
Closing Prayer
O God, the author of mercy, the lover of the salvation of mankind; we address thy clemency, in behalf of our brethren, relations, and benefactors, who are departed this life, that by the intercession of blessed Mary, ever virgin, and of all the saints, thou wouldst receive them into the enjoyment of eternal happiness; through Christ our Lord. Amen.
Concluding prayers: Many novena traditions add one Our Father, one Hail Mary, and one Glory Be at the close of each day's prayer.
Source
https://www.ewtn.com/catholicism/devotions/novena-for-the-holy-souls-in-purgatory-286