Grand Caravan Liftgate

On our 2005 Grand Caravan with 165K miles, the back liftgate has worked fine for years. It continues to raise properly but now it suddenly decided to reverse about one third of the way down when closing button is pushed. Both struts were replaced 3 years ago with the liftgate working fine until now. I don’t see any obstructions on gate or in the mechanism.
Any suggestions?
Thanks

allpar.com is devoted to Chrysler vehicles, past and present. It has a minivan forum which I have found very helpful over the years. Probably someone there can help. Good luck.