The appellant agreed that duty paid by mistake to the government...

The appellant agreed that duty paid by mistake to the government was passed on to the principal contractor under protest. Their argument was that the principal contractor withheld payment exceeding the refund amount to adjust the excise duty paid by the appellant. However, no factual proof was provided or shown that the duty paid by the principal contractor was not passed on or credited against duties payable. The appellant failed to discharge the burden of proving that unjust enrichment did not occur. The impugned order upholding the rejection of refund claims due to the unjust enrichment bar was upheld, and the appeal was rejected.