Default iphone keyboard does not close for entire application if it is opened in iframe in ionic 3

Question

i have used cordova--plugin-ionic-keyboard default plugin in my hybrid ios application in ionic 3 . when i open a payment gateway link by using iframe and i click on the textbox button for writing a card details keyboard will appear but if any case i want to go back after opening a keyboard then keyboard is not closed or hide for whole app then i have to close the app and start again.

i have searched a lot of things on internet but i can not get a appropriate answer which works for me.

i have tried out hide() method of plugin but whichever page i use this hide method that page is not open means app stop before the page on which i try hide method.

i also used in-app browser but still not work