2949591 - BTP CF AppRouter Application error - status 500 - OAuth2 requires \"clientid\" option"

HTML5 XSA AppRouter application cannot be opened in SAP Business Technology Platform (BTP), Cloud Foundry (CF) Environment. Application logs show the following:

[...]
[APP/PROC/WEB/0] OUT <...> <XXXXX>-appRouter","component_instance":-1,"source_instance":-1,"organization_id":"-","organization_name":"-","space_id":<...>GET request to <Business Service> completed with status 500 - OAuth2 requires \"clientid\" option"}
[RTR/1] OUT yvyjza4qglrjnpn1cockpit-approuter.cfapps.<region> - [2020-07-16T13:22:06.506288601Z] "GET <Busines Service> HTTP/1.1" 500 0 21 "https://account.hana.ondemand.com/cockpit" <...>
[...]

• SAP Business Technology Platform, Cloud Foundry Environment
• SAP HANA XS Advanced Model Application Router (XSA AppRouter)
• SAP UI5 HTML5 Application

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