Practical 18650 Battery Box Phone Tablet PC Power Bank with Portable Bag

I've replaced all the 18650 cells from my bose battery and now it won't output any power. I can't find any schematics online, where do I move on from here? : r/AskElectronics

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100% brand new and high quality, ., A DIY power bank box, without battery, needs 2pcs 18650 or 18700 20700 21700 rechargeable battery (Not included),

Portable 18650 Power Bank Case DIY Charging Battery Box for Smartphone Tablet PC

3-Port Input DIY USB Power Bank Kit Box Case 18650 20700 21700 Battery Charger with LED Flashlight for Cellphone Tablet

26800mAh Portable Charger Power Bank, Dual USB w/USB-C Fast Charging Battery Pack Charger for iPhone 14 11 12 13 pro max, iPad,Airpods,Samsung S22 S23 Ultra, Google Pixel 6,LC Android Phone-Orange - Yahoo

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Practical 18650 Battery Box Phone Tablet PC Power Bank with Portable Bag

3.3A 5V-21V Mobile power bank Six 18650 Battery Charger For 19V Laptop 5V iphone

Powerbank using Laptop Battery and 18650 Battery Case