If you have upgraded from the old version 8.8x then you might have encountered the issue where it crashes and update of the app won't process. No worries, you can easily solve it by doing the following steps.
1. Go to your phone settings > apps > Truecaller
2. Storage > clear data
3. Uninstall. Now, reinstall from Google Play.
We're truly sorry for any inconvenience caused. If you have any questions please tap here.