Assistance booking form Air Europa not accessible

The form to request assistance with Air Europa is not accessible

There is a mandatory check box. But it cannot be activated with the keyboard.
The screenreader says that it is checked, but in reality it is not.
I see no way to get around this step, other than asking a mouse user to click it.

Inacessible form: https://www.aireuropa.com/en/flights/manage-booking/request-assistance