Accordingly, it was further contended that the doctrine of unjust enrichment is not applicable in this case in the light of TECIL Chemicals Vs. Commissioner of Central Excise 2003 (151) ELT 136 and also the ruling in the case of Uniproducts (India) Ltd. Vs. Commissioner of Central Excise, Delhi 2004 (170) ELT 299. Further, an affidavit was also filed by the respondent before the Commissioner (Appeals) that they have not realized the differential duty from its customers.