I had pretty much the exact same thing happen in the last 2-3 weeks. This was on my Duo-Shi’s on Shimano SPD bodies. Also recently, the play on the right pedal was getting out of control and the pedal started squeaking and chirping. I took the pedals off, disassembled the spindles, cleaned and greased them up and put them back together. They have noticeably less play and are quiet again.
If you ride through the water at all, I’d recommend pulling the duo-shi’s apart and doing some cleaning on a regular interval. It was pretty easy, and I feel much better riding them.
Link to the service video that I used. A Wild idea for Favero Assioma pedals [MTB SPD Hack] - #908 by Stevie_Dee