Astra van 1.3cdti

Hi all new here so please be kind lol

I have just purchased an Astra 1.3 cdti 58 plate at auction however it's in limp mode, engine light is on and code reads p0101 MAS air flow

Anybody had this before? I've tried cleaning the mas airflow sensor to no avail, everything else on the van seems perfectly fine

Any help would be appreciated also the van has 101000 miles