LCS Inc. Greg Taylor threatened me with court for unpaid Walmart bill. my Walmart account was closed in 2010. orange, California

Greg Taylor from LCS Inc. called my cell phone with a blocked or private number. He wanted to know if anyone would be home from noon-2pm tomorrow so I could sign for court summons for an unpaid walmart account. Apparently, my balance was $1500, with an additional $800, tacked on for court costs. I used to have a walmart account, so at first I believed him. I got basic information from him so I could call and talk to my husband about it. I had a funny feeling about the whole thing. I looked online and got the number for GECapitol., the finance company that holds walmart credit card stuff. The lady looked my information up and told me my account was paid in full in 6/2010. That's over 2 years ago.

She is sending me a letter to prove. So I called Mr. Taylor back and asked his company information again and explained how I've made calls and found out my account has been paid in full. He wanted me to send him the letter to verify, but I told him to go ahead with the summons and I'll take the verification letter to court. He didn't like that idea at all, just kept telling me that if in fact it has been paid, going to court will be a huge waste of time and hassle for me, I told him I didn't mind at all. I tried to call him back again, but the call goes straight to voicemail and the recording recites a different number than the one I dialed.