IAP::init crash with "android key"

Hi,
First of all I’m very sorry about my poor English.

I’m using Cocos2d-x 3.6 and sdkbox-iap 1.2.1 now.
In iPhone I have no problem, but in android IAP::init makes my app crash.

I tested many time, I found the cause.
When I remove the “key” of “iap” under “android”, my app doesn’t crash.
I think I copied my app key right way, and I check several times key.

Now I am using 1.2.1 of iap plugin, but this crashing bug was from 1.1.6.

Is any way to fix this problem, or is there a special way to copy key to sdkbox_config.json?