Automatic gearbox does not accept the D mode

Hi, I have a Citroen c4 year 2005, automatic gearbox. A coupe of weeks ago, I was driving and suddenly noticed that there is no acceleration when I push the accelerator pedal. The cor stopped, and I thought if I switch off the engine and start it on again might fix the problem. I switched off, but could never start up the engine. A mechanic changed the fuse box in the engine compartment, and now the engine can be started up, but the gearbox does not go to the D drive mode, only P, N, and R. The computer does not show a fault. Any experience with this problem?