Fit to fly company recommendations (trip to Italy)

Hi, I will be going to Italy in about 2 weeks and they require UK travellers to show proof of a negative lateral flow test. Most of the fit to fly providers seem quite scammy and have very mixed reviews in terms of people not getting their results. I am going on a very early Monday morning and I won't have access to any regular testing sites before the flight.

Can anyone recommend a trustworthy and cheap fit to fly provider? Or possibly, would the text message from NHS (that you get when you upload a negative self test result) be enough for international travel?