Missing OCN products

[This is not really a S1 Toolbox question, but I thought some of you may have the answer.]

Why is it that every so often the OCN product associated with a given scene is missing? For example, S1B_IW_GRDH_1SDV_20210324T155557_20210324T155622_026159_031F1A_6920 does not have a corresponding OCN product.

Thanks!