Add-on inventory is not a per-registration maximum

Open Events → Events → select your event → Edit Event → Add-Ons.

The add-on editor explicitly defines Total Available as the maximum for the whole event, not per registration. Unlimited removes that inventory cap. This screen does not expose a separate two-per-registration limit for an add-on. Do not set Total Available to two expecting each registrant to get two; that limits the shared inventory. Ask support to review another supported ticket/guest configuration if individual registration limits are essential.