Software update

[Kirstyxx]

Hi looking for a bit of help and information regarding my family car ( Audi A5 2.7 litre) over the past year been having problems with cars performance, car is currently going into lymp mode. Now we have been at several garages and had parts changed sensors changed even a new dpf, car is perfect in parts department but still going into lymp mode and have been told car needs a system update ( not from Audi) can anyone give me any information for people who do software updates on cars please! Thank you