Kano Make Your Own laptop, dead battery replacement/fix

The red kano battery pack in diy laptop no longer powers up the laptop hasnt been used much and is relatively new, (within a year).

when charging it there is 3 steady lights and the 4th flashing which im assuming means 3/4 full but zero output of power from the usb.

I tested the mini usb cord with my phones power bank and there were no issues and I tested powerbank with a usb light to prove problem is the Kano battery pack.

Anyone else had these problems? Can replacements be bought or does someone know anyway to fix?