If you have the Littledata Google Ads connection enabled, follow the below steps to disable the connection and unlink the accounts:

Step 1. In the Littledata app, go to the Connections tab, then click Disconnect on the Google Ads connection:

Step 2. Delete the account linking from your Google Analytics; go to Admin > Google Ads Linking. Click on Littledata Google Ads Connection. Then hit Delete link group:

Step 3 (optional). If you opted-in for remarketing audiences, you can delete the audiences added by Littledata. Go to your Google Analytics Admin > Audience Definitions > Audiences:

Open the audiences and click Delete Audience for each:

You have now disconnected the Littledata Google Ads connection.