Query with index hint don't give back a result

Hi

i have this problem

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SELECT /*+ index(t indexname) */ *

 FROM schema.tablename t

WHERE t.colum name = 3453454534;

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returns zero rows

the query without index hint

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SELECT SELECT /*+ parallel (t,16) no_index(t) */ *

 FROM schema.tablename t

WHERE t.colum name = 3453454534;

----------------------------------------------------------------

give back 3 rows

Database Version Oracle 18C

now is the question,

is it a failure in the script,

exist some known bugs!

br