Activation Lock Trouble

Hi,

I used to use an old iPhone 4s, linked with my icloud address, however it's been years since I accessed this device and today I want to access my phone in order to transfer all the old data to my laptop. However when I turned the phone on, there is a notification said that my phone linked to an icloud address that i'm not familiar with.

I try to seek a solution for this but the only advice available is only to contact the previous owner. For me this is an impossible tasks since I brought this iPhone back in 2014 and it's been to long to track the previous owner.

When I check my iCloud pages, this phone is still listed as one of my phone. Is anyone know how to restore my data back and accessing this iPhone? This thing seems simple but it matters for me since there are lots of photos from the past that I wish to restore.

Thank you