Garage probably deleted all error codes when doing the MAF sensor.
It would have been helpful if they had shown you a printout of all error codes they found.
Normally after new parts fitted another code read is done to confirm problem fixed.
There are cheap code readers for less than £20 around , but many on Fiat Forum use
MES (
multiecuscan) diagnostic tool and can advise you on the results from that.
Read the hand book regarding the display messages if only to rule out any extra confusion.