pem.disableSubscription API call fails with the error:
Internal error: APS suspendable resource '39b2f307-2ac3-46b1-9e08-cd27d47a4d0c' was NOT disabled.
This causes a cancellation order failure in Billing with the error:
Removing of Service of Subscription #1000100 is failed. Stop service of Order Item #1111123 failed.
/var/log/pa/core.log there is a 500 Internal Server Error response from the endpoint server of the corresponding APS application:
Mar 14 17:57:45 osscore : INF [openapi:192.0.2.2:10663 1:5108:3230 SAAS 737834912]: [ HTTP] OUT endpoint.example.net  "PUT /endpoint/organization/39b2f307-2ac3-46b1-9e08-cd27d47a4d0c/disable HTTP/1.0"  "500 Internal Server Error" 6359ms
The APS application that is provided inside the subscription experiences a failure during the call to disable the subscription.
The issue lies on the APS application level, so it is necessary to investigate the log files on the corresponding APS endpoint server to find out and resolve the reasons behind the error.
See the following article for more details on APS 2.0 logging: APS2 logs