3723256 - JOULE throws the error "Processing Error: The service is currently unavailable. Please reload or contact your administrator"

After completing the activation process for a JOULE service, the error message "Processing Error: The service is currently unavailable. Please reload or contact your administrator" is encountered.
In the network traces, below error might be logged:
**********************************************************
"error":{
"message":"Network Error"
"status":"ERR_NETWORK"
"code":"DEFAULT"

Network Error
Failed to load resource: net::ERR_HTTP2_PROTOCOL_ERROR
No response to read CSRF Token from header

***********************************************************
Similar issues can also occur when Joule for Consultants is used.

• SAP Business Technology Platform (BTP)
• Cloud Foundry runtime and environment (CF)
• Joule

processing error, service unavailable, sap successfactors, network issue, activation error, connectivity problem, sap btp, cloud foundry, ias domain, ip ranges, troubleshooting, Processing Error: The service is currently unavailable. Please reload or contact your administrator , KBA , CA-JOULE , Joule , CA-GAIF-SCC , SAP Joule for Consultants , Known Error