what is done with measurements?

Hi everybody! I attached a file with s parameters of an amplifier. The red line corresponds the data that were given by manufacturer of the amplifier. Some fellows from a lab have done the measurements of this amplifier and have got what we see is drown by blue line. It seems to me, the measurements weren't done correctly. Also, as we can see the shape is similar but only turned. What the mistake during the measurement could entail this results? Thanks a lot!

nobody knows?

This is typically due to deembedding error.

It seems that a phase error occurs, it depends on the test ficture you used, maybe somthing wrong was done.
Did you do deembedding after measurement ?

If not, the calibration is wrong.

Thank you for the feedback. I don't know what is deembedding error. Is this something like calibration?
Can I simulate this effect in ADS, for example?

You can place a lossy transmission line model before s2p element in ADS (with the result of manufacturer meaurements data) and tune parameters of the transmission line model to get the same result as yuor lab data. It seems like the data of manufacturer are deembeded and your data are not.