Ddo you still have the seed packet?
Was it a reputable company or a non-name?
Does it provide the scientific name?
Does it say anywhere on the packet what country the seeds were packaged?
...another thought -- grown as companions for hot peppers, they may have been given too much fertilizer and too much rich soil and water. Herbs like oregano have more concentrated fragrance and flavor when grown in gravelly/sandy, lean, well draining soil with less water.
Sometimes companion plants are better considered "working plants" and it's better to plant "harvesting plants" in their ideal locations. This may have been one of those cases.
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