If you have the Littledata Facebook Ads connection enabled, follow the below steps to disable the connection.

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

You will now stop receiving daily cost data imports to your Google Analytics account.

Step 2 (optional). Delete the import files from your Google Analytics account. Go to Google Analytics Admin > Data Import > click on FACEBOOK LITTLEDATA IMPORT > select the files you wish to delete and hit Delete Selected:

You have successfully disconnected the Littledata Facebook Ads connection.