At google trip page they said:-
We’re saying goodbye to Google Trips August 5, 2019. Many of your favorite features will live on in other Google products. Learn More
Google Also mentioned at their support page https://support.google.com/travel/answer/9337634-
Important: Support for the Google Trips app will end on August 5, 2019. At this time, you’ll no longer be able to use the app.Until then, you’ll still be able to access and email all of your trip reservations and notes as normal.
Image Credits: Google Trips