The Google Tasks API has a courtesy limit of 50,000 queries per day.
Depending on your project's resource usage, you might want to request a quota increase. API calls by a service account are considered to be using a single account. Applying for an increased quota doesn't guarantee approval. Large quota increases can take longer to be approved.
Not all projects have the same quotas. As you increasingly use Google Cloud over time, your quotas might need to increase. If you expect a notable upcoming increase in usage, you can proactively request quota adjustments from the Quotas page in the Google Cloud console.
To learn more, see the following resources: