Morning Michael
Welcome to the Forum
You say a New Battery was fitted so a couple of questions first 1. Is the battery correct for the car ? 2. Was the battery correctly registered to the car.
If the battery is incorrect or not registered correctly it may not be charging correctly and low voltage is a possible trigger for the message, you are seeing. Another could be lots of short journeys where the battery can't recover. After start it needs at least 20 mins driving to bring it back to full charge. Test the battery at the charging points under the bonnet you should see 12.5v to 12.8v with the engine off 14.5v to 14.8v withe engine running.
If all is OK with the battery, what miles have you covered and when if ever was the gearbox serviced.
Good Luck
Dave