Discrepancy
Any mismatch between your documents and a letter of credit's terms. Grounds for refusal, however minor.
Common ones: a goods description that does not correspond to the credit, late presentation, a transport document of a type the credit does not permit, insurance for the wrong amount, and inconsistency between documents on weights or party names.
A refusing bank must give a single notice listing every discrepancy within five banking days. It cannot refuse in instalments, so one it fails to mention is waived.
Where you can correct and re-present inside the presentation period and before expiry, do that. Otherwise the buyer waives or does not, and that is a commercial conversation.