How do I talk to someone about getting my permanent residency card renewed after it expired and told gone long?

I lived in the U.S. for 42 years and returned to U.K. to photograph birthplace and found that green card had expired before I had left the U.S. I was told that I had been gone from U.S. too long and would have to wait 6 to 10 years to get another green card.Can you help me? All my family still lives in the U.S. and I was the only family member who kept their green card.