Edit, delete or restore a customer or supplier

Open Settings, under Shortcuts, Contacts, and click the contact's row. Owners, admins and accountants can change and delete contacts; a bookkeeper can change them but not delete; all other roles can open a contact but only read it. Changing a contact's IBANs needs an owner or admin, and every IBAN change is reported to the owners by e-mail.
Change what you need: Name, Type (company or person), Customer and Supplier (at least one must be ticked), Business customer (B2B), Related party (shareholder or group company), VAT ID, Country (ISO code), Street, Postcode, City, Email, Leitweg-ID (public sector), Document language, Default payment terms, Default category and IBANs (one per line). Then choose Save. The e-mail address is needed to send invoices and dunning letters to the contact, and a Leitweg-ID makes invoices to the contact XRechnung e-invoices.
A save can be refused with a message that says why: an invalid VAT ID, an IBAN with a wrong check digit or length, payment terms that no longer exist, or Someone else changed this contact meanwhile. Reload and try again. when a colleague saved first.
A contact nobody has confirmed yet shows Proposed, please confirm next to its name. Open it, check the data and choose Confirm.
To delete, open the contact and choose Delete, then Yes, delete. If bookings or other records use the contact (invoices and other sales documents, dunning letters, recurring invoices, VAT ID checks), it is archived instead: Bookings reference this contact, so it was archived instead of deleted. An archived contact leaves the list.
To bring an archived contact back, tick Show archived, open the contact marked Archived and choose Restore. A contact that was really deleted (nothing used it) cannot be restored in the app.
The list under Settings, Contacts shows every customer and supplier one page at a time, with the tabs All, Customers and Suppliers, a search over number, name, street, city, e-mail, VAT ID and tags, a tag filter, sortable columns and a choice of rows per page. Show archived includes archived contacts. Import next to New contact brings contacts in from a file.
A click on a row opens the contact's form. Open full page (turnover, documents) in the form's heading opens the contact's own page with Overview, Turnover and History. Turnover shows the net turnover of issued invoices and corrections of the last 12 months with what is open and overdue, and needs the right to read it; History needs the right to read the audit log. New document starts a document for that contact and needs the right to create documents. Changing a contact happens in its form; on the contact's own page Edit in Settings leads back to it.
Roles without the right for sensitive settings see IBANs masked (country, check digits and the last four characters) and cannot change them. A VAT ID or IBAN that another contact already holds is refused the same way as on creating; saving anyway is recorded.
On the Contacts tab, roles with the export right find Export contacts (CSV) for all contacts, and Export data (JSON) on one contact gives everything stored about that contact (data access and portability, Art. 15 and 20 GDPR). Both exports are recorded.