Need Help Unlocking My Deceased Mum’s Phone

Hey everyone, I'm reaching out for some advice. My mom passed away last year, and I've recently gone through her belongings. One item I have is her Oppo A53 phone, but it's locked with a passcode, and I can't figure it out. I've already contacted Oppo support, but they can only offer a factory reset, which I really want to avoid. We're looking for any data that might help us understand what led to her decision. If anyone knows of a program or method to unlock the phone without losing the data, I would really appreciate your help. Thanks a lot!