Notice of seizure for CBD oil

I received notice of seizure for a CBD oil that I ordered online due to ''containing THC''. On the website, there is no mention of THC and when I contacted the store they confirmed there is no THC (although admitted that very minimal traces can be sometimes found in CBD oil). They also mentioned they regularly ship to Ireland and never had any issues with customs. In the Revenue letter there is information on how to appeal in writing, so I plan to write to them. Any tips on what should I write to them in the notice of claim? Is there any point to appeal?