im new in Angular and I'm trying to make site with list of books (with properties a,b,c,d) and where u can add new book. 1st time when i submit everythik goes fine and 2nd time i get this error v2.newBook is not a function. Does anyone knows why its working 1st time and 2nd time not? Thx

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`https://plnkr.co/edit/OtfLPuQFptfgUxuo0pXJ`

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