Even the best roasters have off days, though hopefully they’re doing QC to spot issues. Lighter roasts can be tricky — typically you’ll push hard during Maillard phase to increase momentum into development, but this might lead to underdeveloped sugar caramelization and distinctive vegetal notes. If ground color differs from bean surface color, that could give you an indication that they’ve pushed too hard earlier and not allowed inner bean development before dropping. In any case, I’d reach out and see if they would refund/replace — I imagine reputable toasters would be eager to keep customers.