Solo accounts and Team Admins/agents with the correct permissions can delete contacts. If you follow these instructions and you do not find the delete option, you do not have permissions and should contact your team admin.
Note: Delete all removes all contacts in your database and not just from the folder you are in. These may not be able to be recovered .**
Contacts tab in the top, select the folder you want to view on the left hand side and then select the contacts you wish to delete.
2. Use the More drop down to select delete and then either Delete selected or Delete all.
You can delete all contacts in a folder by choosing the checkbox/dropdown and choose to delete all in a folder by selecting the bulk select option.