Excess Assessable value

A business has been charged excess IGST due to an incorrect assessable value used by the customs department. The user is asking if this excess IGST can be claimed as input tax credit for their business. Another user suggests that any IGST paid can be claimed as input credit or refunded by Customs. The original poster clarifies that while the invoice value is correct, the assessable value is wrong, leading to an incorrect IGST calculation, and questions the implications of claiming this amount in GSTR-3B.