Inquiry about maintaining refreshtoken in gmail api of oauth 2.0 playground

Question

I read that the refreshtoken is automatically revoked every 24 hours in the gmail api of the oauth2.0 playground. To prevent this and keep it going, we ask if there is a product that needs to be subscribed or paid for, or if step 3 is performed, it will be maintained indefinitely. If it's not a way to pay or subscribe, but a way to do step 3, I'd be very grateful if you could tell me how to do it.