docs: call out unsupported Azure subscription types on supported payment methods page (#61033)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: crwaters16 <78226508+crwaters16@users.noreply.github.com>

Author: Copilot

content/billing/reference/supported-payment-methods.md

@@ -31,6 +31,19 @@ Accounts with volume licenses and metered billing can use multiple payment metho
 
 {% data variables.product.prodname_copilot_short %} standalone accounts, which traditionally used Azure Subscription IDs, can now also pay by credit card. Contact your {% data variables.product.github %} representative for details.
 
+## Unsupported Azure subscription types
+
+The following Azure subscription types cannot be used as a payment method for {% data variables.product.github %}:
+
+| Quota ID | Offer number(s) |
+|---|---|
+| `FreeTrial_2014-09-01` | MS-AZR-0044P |
+| `AzureForStudents_2018-01-01` | MS-AZR-0170P |
+| `DreamSpark_2015-02-01` | MS-AZR-0144P |
+| `AzurePass_2014-09-01` | MS-AZR-0120P, MS-AZR-0122P–MS-AZR-0125P, MS-AZR-0128P–MS-AZR-0130P |
+| `PayAsYouGo_2014-09-01` | MS-AZR-0017G |
+| `Sponsored_2016-01-01` | MS-AZR-0036P |
+
 {% ifversion fpt or ghec %}
 
 ## Usage-based billing availability