In-app purchase ionic 3

I have my app on ionic-v3. I’m integrating ina-app purchase
but when installing it with cordova plugin add cordova-plugin-purchase --variable BILLING_KEY = “my-key” my project removes the native libraries even the splash and the generated imaneges all return to the splash images even icons defaults to ionic. How could I integrate this library if I have problems, and without my project?

my version :
ionic info

cli packages: (C:\Users\Christian\AppData\Roaming\npm\node_modules)

@ionic/cli-utils  : 1.9.0
ionic (Ionic CLI) : 3.9.0

global packages:

Cordova CLI : 8.1.2 (cordova-lib@8.1.1)

local packages:

@ionic/app-scripts : 3.2.3
Cordova Platforms  : android 7.1.4 browser 5.0.4
Ionic Framework    : ionic-angular 3.9.3


Node : v11.11.0
npm  : 6.7.0
OS   : Windows 10