I presume you are on a Residential service ... so talking to Tech Support will be a battle!
The stats suggest that you only have a 6dB noise margin and that is what is holding it down as with your downstream. It just looks a little suspicious - does it ever vary?
Your downstream is similar to mine - achievable 59, so I would have expected to see something above 15 for upstrream, unless there is a massive band of noise right on the U1 or U2 band of tones.
Can you get a plot showing each Tone with the bit loading, attenuation and SNR? That would be useful.
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