I'm sorry to hear that.
My experiences with their customer service can only be called top-notch.
They reply to emails within minutes, and they replaced my first monofin without me asking when it cracked.
May I ask when you bought your tail?
Mine had the older monofin version, which was quite flimsy.
Those tend to break fast (although I have a second one which holds up fine so far, fingers crossed).
The newer fins are thicker and more sturdy, so if that one broke, they probably assume you didn't handle it carefully enough.
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