Yes, it is true that one has to necessarily experience for one’s past actions and hence experiencing destiny is unavoidable. But what about the actions of the present, which will translate into future experiences? Are they not important?
You should pray to God not to liberate you from the actions of the past but to give you strength to endure them with fortitude!
This is exactly what the Guru helps the devotee to achieve. He becomes his friend and then guides him in his joys & sorrows; He prevents the devotee from further falling down. The devotee may fail in worldly sense but the Spiritual Master will ensure that he does not fall spiritually.
There is essentially no difference between your inner Self and the external manifestation of God. So when you pray, you merely humble down to your own inner Self. You are praying to your own inner God for your own upliftment.
(Bhaktimala Jan 1977)