I suspect the vehicle has ABS and the electro-hydraulic control unit needs to be bled. This is to be done if there is a possibility that air got in it. Note, it should be done prior to bleeding the brakes, otherwise, you won't have a brake pedal.
If you look below, I attached the directions for the procedure. Give this a try and let me know if it helps.
See pics below.
Images (Click to enlarge)
Monday, November 22nd, 2021 AT 9:19 PM