No JOIN Predicate

I received a response to a scan with a higher level of priority: 

No join predicate has been detected


Below is the SQL that triggered it. I personally do not see an issue with it. Can someone point me to what exactly is triggering the response?



UPDATE #tmpTable24_78Receipt

SET AssessmentNumber =

(SELECT TOP 1 assessment.assessment_number

FROM tender

INNER JOIN tender_detail

ON tender_detail.tender_ID = tender.tender_ID

INNER JOIN assessment_detail

ON assessment_detail.assessment_detail_ID = tender_detail.assessment_detail_ID

INNER JOIN assessment

ON assessment.assessment_ID =assessment_detail.assessment_ID

INNER JOIN xref_assess_case

ON xref_assess_case.assessment_ID = assessment_detail.assessment_ID

WHERE tender.payment_ID = #tmpTable24_78Receipt.payment_ID

AND xref_assess_case.case_ID = #tmpTable24_78Receipt.case_ID)