If you think that it is a material failure and the jacket is newish, I’d suggest submitting a warranty claim with MH here https://www.mountainhardwear.com/on/demandware.store/Sites-MountainHardwear_US-Site/en_US/Warranty-S.... If it’s an older jacket it may be repairable with a flexible adhesive like aqua seal or SG-20. 

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PDB
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