What about an alternative?
Instead of complaining to the landlords if they're not receptive, can you instead speak to the neighbours themselves, explain that they are keeping you up with their noise, and come to an agreement between you? Say, no noise after 11pm except friday/saturday if they are party people and want to party?
There could be compromises made, instead of pushing to have it all exclusively your own way.
Perhaps the landlords have had experience with people with silly demands? I know one ongoing neighbour dispute a relative has, and she tries to stop any of the neighbour's guests parking on the road outside her house. It's a public street. This is obviously not reasonable. That's equally obviously not what you are doing, but maybe they're lumping you in with people like that? That they see anyone with a complaint as being unreasonable because of past experience?
If you could resolve it without them involved that might be better if they're going to punish you for a complaint.
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Alexithymia - 147 points.
Low-Verbal.