Border agent took my Green Card

Update: I got my Green Card Back 🎉🎉 And all thanks to my super lawyer!!! If you want her name, just sent me a DM. She sent them a letter, called and it worked!

Yesterday I arrived at the airport and was stopped at the border control. They took my green card and issued form I 94 with stamp I 551 and a parole both of the until Dec. They asked me to come back to the airport in a month to bring my divorce papers because I got my green card through a marriage. I asked them why they are tacking my card, since I never ever had this problem at the arrival and I’ve been following all the immigration rules, had a real marriage(unfortunately it just didn’t worked out) and I’ve been paying taxes and etc. They responded: “We need to verify your green card” Is it normal? I’m very confused.

What should I do? Should I hire a lawyer and go with them to the meeting next month? I have all the documents with me already.

EDIT: Thank you to everyone who offered hope and helpful advice today. I’m truly grateful! It’s been a challenging day, but with your support, I’m in a much better state of mind. I’ll update after Dec 10th.