You can easily view or obtain an invoice or all your invoices directly in your WebSelf account.
To do this, go to the avatar tab located on the right side of the Dashboard and click on My Profile.
Click on the Billing and Payments sub-tab; here are your options:
SUBSCRIPTIONS
In this section, you can view information about your subscriptions: Status, Last payment date, Next payment date, Subscription cycle, and Payment method.
BILLING HISTORY
In this section, you can view information about your invoices: Payment date, Description, Site, Amount, Status, and Bill (available for download in PDF format).