A quick google search for Am7b9 (I picked "A" arbitrarily) shows this:

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Am7(b9) Guitar Chord
Am7(b9) Guitar Chord. 4 chord voicings, charts and sounds. Chord notes and structure: A Bb C E Ab (R m2 m3 5 7).

Am7(b9) Chord
Standard name: Am(maj7)b9
AKA: Am(+7)b9; Am(+7)b7/9; Am(maj7)b7/9; Am(+7)b7/9;

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Maybe one of the AKA's would work.
Good luck!
LLOYD S