Not an expert using Google Sign up/ Log in, but often some tokens that are given have a lifespan and expire after some time.
Maybe you need to have another API call to get a token (usually a POST request that has some kind of authentification aswell), and use this API call in a workflow to then pass the valid token.
example:
1/ POST url/generate/token → gives you the token
2/ Google Login/Signup using result of 1/'s token
Hope that can give you some hints for further research 
(by the way usually when something doesn’t work anymore, there is a reason 
)
Forum
Academy
Marketplace
Showcase
Pricing
Features