transact returned transaction_id and block_num, by passing the block_num to get_block, I got an empty transactions array.

[fintechee]

eosjs v21.0

transact is done without error and returned transaction_id and block_num.
But, by passing the block_num to get_block, I got an empty transactions array as below:

{"timestamp":"2020-12-21T21:55:44.500","producer":"jungleswedem","confirmed":0,"previous":"07af862f94ed2f28b68c01210cf53da30c7772c98c578a4fb1d5ab0b6af273b5","transaction_mroot":"0000000000000000000000000000000000000000000000000000000000000000","action_mroot":"25908188d6a6e030e9374bdb694f23f3211d10635e16813e0e3c50fcb7632cae","schedule_version":404,"new_producers":null,"producer_signature":"SIG_K1_Kj5grPti2N7ncPuCZsiVa3q346aSYRxvfepiPo6fY4aYt9Cipv14vGLT6Ex1FDyxafWFMoEDTMHc9hXTFqkfGFTTTo54n1","transactions":[],"id":"07af86308489c1745192cf84899b370c081651cdb09fcf44894e880e9e1f2c4c","block_num":128943664,"ref_block_prefix":2228195921}

128943664 is the return value that transact gave back to me.

Please tell me how to confirm whether a transaction is done 100% successfully.
Many thanks.