shudder

So it happened. My 2022 Bronco Sport BB started to make a shudder and chattering noise on the RDU. My wife noticed it a couple of days ago. Thought it was the parking brakes grinding or rubbing against the discs and making the noise because of some surface rust on the discs due to the weather...

I’m having a transmission shudder at 30-40mph and again at 50-60mph. They replaced the torque converter, it took 2 1/2 months to get the part. They said it was all fixed but the shudder is still there. Anyone else had this problem and what did they do to fix it?