Deuteronomy 18:10-12 There shall not be found among you any one that maketh his son or his daughter to pass through the fire, or that useth divination, or an observer of times, or an enchanter, or a witch, Or a charmer, or a consulter with familiar spirits, or a wizard, or a necromancer. For all that do these things are an abomination unto the LORD: and because of these abominations the LORD thy God doth drive them out from before thee.
Necromancer
One who pretended to discover unknown and future events by summoning and interrogating the dead, De 18:10-11, a crime punishable by stoning to death, Le 20:27. See SORCERER. No good reason can be given for believing that such pretended communications with departed spirits are less offensive to God now than in the time of Moses.
American Tract Society Dictionary
Praying to Mary is not only idolatry, it is necromancy. God's Word declares it to be offensive and an abomination. Such a crime merited death in the Old Testament Law.
The New Testament declares there is but one mediator between God and man... the man Jesus Christ.
Praying to Mary is iniquitous. And the psalmist declared that if one regards iniquity in one's heart, God will not hear that one.
Your prayers to Mary are both foolish and vain.