I have a scheme certificate from my past employer, issued in 2006. I started employment with the current company in the same year. When I left the first company, I withdrew my PF amount. However, due to completing 10 years of service, I was issued a scheme certificate. My previous employment did not have a UAN, nor was it linked to Aadhar, and it was closed in 2006. Upon joining my current job, I did not submit the scheme certificate. How can I link my old scheme certificate to my current UAN?