All good - it looks properly tuned - but probably best to not display all the traces once. You only really need the blue and yellow. Otherwise it gets confusing.
The blue is S21 - the transmission through the filter received at port 2 from port 1. Seems you have a loss of about 0.7dB That's at 2397MHz which is very close to the ISS frequency. It is also the centre of the pass band. You need to decide if that's where you want it centred, which will probably depend on what side of the wanted band the interference is strongest. It if is coming from 5G at 2390MHz, you might want to offset the pass-band a little higher. Conversely if it is coming from the Wifi, the opposite. If in doubt, leave it where it is. You want as little ripple on the flat part as possible, but there will usually be some. There is a trade off between ripple and how steep the cut off is.
The yellow trace S11 is the return loss, what port 1 gets back as a reflection of what it sent. This needs to be as little as possible to have a good match in band, but it won't be perfect and -17 dB will be good enough. That's 1/50th of the power reflected. Outside the pass band the power should be almost all reflected. That's how a filter works. You will find out that you can get a very good match at some frequencies but anything better than 10 dB is likely to be good enough for most cases. It's equivalent to a 2:1 VSWR, which most PAs can cope with.
The purple trace is the phase. That looks right. In the pass band you want it to be changing linearly with frequency, (i.e. a straight line, not a curved line) which it is. OK in the middle it looks like a big transient but that's just an artefact going round the circle. These filters tend to be less linear near the edges of the pass band. I am not sure if you are looking at the transmitted or reflected phase response, I think it is reflected. I will have to find my NanoVNA to be sure. You might also want to look at the group delay.
The green trace is the smith chart. It shows the impedance of the filter. The chart is showing the resistive and reactive part of the impedance. The centre of the chart is 50 ohms resistive, (assuming you are using 50 ohms). Horizontal line through the centre represents the resistance from 0 ohms (short circuit) to infinite (open circuit). If the measurement is not on that line, it has a reactive element. If the measurement is above the horizontal axis, the match is inductive - i.e. it looks like a resistor with an inductor, if it is below that line it is capacitive. That's not much help here but it would be useful information if you were say tuning an antenna. Now is probably not the time to explain Smith charts. This is great resource.
https://www.microwaves101.com/encyclope ... art-basics
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