What do these errors mean?
Groove, as well as other Salesforce integrated apps you may be using, utilize API calls to gather information from your Salesforce org, such as data to populate merge fields in Groove templates.
Each Salesforce organization has a maximum amount of API Requests allowed per 24 hour period. If that limit is reached, Groove and your other integrated apps would not be able to gather the information they need from your Salesforce, until the API Requests reset, or until you increase the amount of API Requests your Salesforce organization has.
Finding information around your team's API Calls
In SFDC Setup, use the Quick Find to search for 'Company Information'. On this page, you'll see how many API Requests have been made for your org over the last 24 hours, as well as the max amount allotted to your organization:
You can also report on your team's API usage to understand usage over a period of time. Here's a Salesforce article going into more detail on this!
How to resolve these issues
If your team runs into issues with API Call limits infrequently, we'd recommend requesting a temporary increase to your API limit with Salesforce when the issue does arise.
If you find that your team is very frequently running into these issues, we'd recommend requesting a permanent increase to your API limit.
Here's the SFDC article explaining how you can go about increasing your team's API limit.
Please contact email@example.com if you have any additional questions!