If you used to successfully connect to SightCall but suddenly are unable to connect to SightCall and are getting stuck at "Error connecting to SightCall" and/or "An error occurred", "Your package is not activated yet" or "401 - Api Key seems to be invalid" in an integrated environment (Salesforce, Zendesk, etc.), then it is possible that the API Key for your SightCall tenant has recently changed which causes the existing integrated environment package activation to no longer be able to connect to your SightCall tenant.
To fix this issue, please get your SightCall Administrator involved to gather your tenant API Key and provide it to SightCall support so the existing package activation can be deleted and reactivated.