Check RFC Destination for correct Target Host, Service No. and Path Prefix (proxy), ensure a target system username and password is defined, SEE 4.1.3 RFC Destination
Check /BTI/TE_INT_SYST that correct RFC Destination is defined, SEE 4.1.2 External System(s)
Check /BTI/TE_INT_POLH that the url points to Jira API, e.g. use Jira’s REST API (not /issues/?filter=10600, but /rest/api/2/search?jql=filter=10600), SEE 4.2.2 AC Polling Header
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