Hello,

I cannot subscribe to the Collections product in the sandbox. The subscription
request fails server-side with HTTP 400.

Steps to reproduce:
1. Log in to momodeveloper.mtn.com
2. Go to Products > Collections
3. Enter a subscription name, accept the terms, click Subscribe

Request:
POST /developer/users/<my-user-id>/subscriptions/<id>?api-version=2022-04-01-preview
Response: HTTP 400 Bad Request

{"error":{"code":"ValidationError","message":"You've reached the maximum number
of Subscriptions (25000) in Product. Please delete one or more Subscription(s)
from Product to continue, or consider upgrading your plan to increase the
limit.","details":null}}

My account has no subscriptions at all — the page shows "You have no
subscriptions yet". The 25000 limit is the Azure API Management cap on the
Product itself, not on my account, so there is nothing I can delete on my side.

Could someone on the MoMo team clean up stale sandbox subscriptions on the
Collections product, or raise the APIM tier? The same question applies to
Disbursements if it is affected.

I am building a rotating-savings (tontine) application and need Collection and
Disbursement to run an end-to-end sandbox payment.

Thanks.