What to do if you have wronged someone and never got the chance to apologize to them?

When I was younger I accused a Christian girl in my class for kissing another girl even though I didn't see her do it, and she got in trouble for it. I don't know if they believed her when she said she didn't do it or not and I don't know how it and if it effected her. I grew up and now I feel so horrible for that and I want to apologize to her but the thing is that she left the school and I also changed school and now I have no idea where she is and I can't apologize to her. What do I do? Should I ask for forgiveness or will I not be forgiven at all? Or should I make dua for her? Because one of the major sins is accusing a chaste woman of Zina and I did that when I had no idea and I regret it now I'm also worried if I have caused problems in her family because of this