Previously connected to the same environment
If you were previously able to connect to SigthCall within Salesforce, check the troubleshooting steps outlined here: https://weemo1.zendesk.com/hc/en-us/articles/360039781251
Previously connected to a different environment?
If this is not the first time connecting to SightCall (in Salesforce or in a standalone environment), it's possible that an account with the same login was already created in a separate Tenant/environment, you will need to ask your SightCall admin to delete it in the other Tenant before continuing.
First time connecting/setup
If this is the first time connecting, or the first time connecting from this specific Salesforce environment, ensure that the person in charge of the Salesforce configuration has enabled SightCall for your account.
Mou can check that the proper configuration has been set by checking the documentation available here: https://salesforce.sightcall.com
Specifically, make sure you are a Service cloud user.
Still not resolved?
If none of these steps helped, feel free to submit a ticket and our support team should be able to help you.