John Gill Commentary Leviticus 19:21

"And he shall bring his trespass-offering unto Jehovah, unto the door of the tent of meeting, even a ram for a trespass-offering." — Leviticus 19:21 (ASV)

He shall bring his trespass offering unto the Lord
To the priest of the Lord, to offer it for him; he, and not she, as the Targum of Jonathan has it; (See Gill on Leviticus 19:20): unto the door of the tabernacle of the congregation ;
where all offerings were to be brought, (Leviticus 17:4Leviticus 17:5) ; [even] a ram for a trespass offering ;
which was the usual creature for such a sacrifice, (Leviticus 5:15Leviticus 5:18) (6:6) ; the woman was not obliged to bring any, she being a bondmaid; and so having nothing of her own, but what was her master's, her circumstances are considered, and scourging was sufficient.