Unhappy passengers with a certain plane

[spelele49]

Hi

How do you with a situation when passengers just don't like to fly with a certain plane? These planes are new but their flights are doing okay, not excellent.

[Tha_Ape]

Not sure what you mean.
Might be that they are "too small" (for example flying LHR-JFK with an A321LR, or JFK-MIA with a Beech). In this case fly something bigger, it's only too small for this range.
Might be that RI (route image) didn't build up yet. In this case you only have to wait.
Might be that your departure and arrival times are suboptimal (between 0000 and 0455 is the worse).
Might probably be other things as well.