Putting in my two weeks

I recently got promoted in my other job and Petco conflicts with my other jobs schedule. (I am part time in Petco and full time somewhere else) but it moved so fast I just don’t know what I should tell them. I am a little afraid only because I don’t know if they’ll let me finish my two weeks. I go in 7-4 in my other jobs schedule and Petcos schedule no longer aligns with me. They schedule me 3:30-9:30 or 4:00-9:30. Any tips? Thank you ;-;