Marketplace invoice download
Microsoft Account can sign in "http://account.micosoft.com" to download marketplace invoice. However, this portal does not allow "Work/school account".
Many customers need invoice or related billing document to reimburse. Please consider to :
1. Let customer can use work/school account to sing in account.microsoft.com
2. Enable customer to download marketplace invoice in Account portal or Azure portal.
Tina Wu commented
3. Send marketplace invoice directly to customer via email