Battery charging problem with Costco Kirkland 10.0

[sterei]

The phonak charger is compatible and cheap on ebay, I bought a 2nd one for my P90Rs for about 25U$.
See also here:

Do Phonak chargers work with the Kirkland KS10.T?

I have the phonak mini charger for my KS10s. Works great. I also purchased the phonak battery pack, which works with the Costco charger. The phonak battery pack happened to be $25 cheaper on Amazon than ordering one from Costco.