I dealt with the previous question for you.
You are going to have to find the owner, it’s a simple as that. Otherwise you are faced with 10 years.
Any competent tracing agent will be able to find the owner. There are lots of them on the Internet.
Here is one advertising and tracing service, no find no fee for about £50 plus VAT. Some will only take instruction from solicitors or will want money upfront..
if that fails, then you can only try adverse possession and wait the 10 years.
Can I clarify anything else for you?
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