Video report and article by Greg Hoare.
The head of a major seafood company in the Scottish Borders says Brexit has "more or less finished" his business.
DR Collin is the biggest employer in Eyemouth, with around 200 workers. James Cook, the firm's Managing Director, says since the Brexit transition period ended they have been unable to export fresh shellfish to the EU, the company's main market.
The problem is the mountain of paperwork seafood exporters have to complete, ranging from obtaining health certificates (each one can take hours per shipment), to completing customs documents.
Much of this paperwork is new, and as full details of the UK's Brexit trade deal with the EU were only published hours before the deadline, companies say they haven't had time to prepare.
One mistake can mean delays, and can even see shipments being turned back at the border.
James Withers, the head of trade group Scotland Food & Drink, says this is particularly damaging to seafood companies, who have to get a fresh (sometimes live) product to its destination within 24 hours.
DR Collin is one such company, and Mr Cook told Representing Border "it's more or less finished the business. We can't sell anything. The UK market as we know is closed at the moment, and our European market for our premium product, that's closed as well, we can't get anything out of the country."
A UK Government spokesperson said it is working closely with the seafood industry to resolve any problems, but urged exporters to "check they have entered in details correctly."
It went on to say "we urge the Scottish Government to ensure they have appropriate staffing levels in place at hubs in their area to certify documentation and ensure there are no delays."
That response infuriated Mr Withers, of Scotland Food & Drink, who said "for any minister to say businesses weren't prepared, would suggest they're detached a little bit from reality."
He called for an end to "political mud-slinging", and urged the governments to fix the issues affecting businesses immediately.
Other industry leaders agree something needs to be done, and say financial compensation will almost certainly be necessary.
Simon Macdonald, Chair of the West Coast Regional Inshore Fisheries Group, said fishing businesses have faced a "perfect storm", and more support was essential.
It isn't just exporters who are affected, but also the individual fishermen who supply them.
The head of DR Collin says he's doing all he can to keep local fishermen in business, but has had to ask some to stop fishing, because he won't be able to sell their product.
Frazer Scott is a lobster fisherman in the village of Garlieston, in Dumfries and Galloway.
He's also Chair of Galloway Static Gear Inshore Fishermen's Association, and says he, and many others, are not going to sea this week, because there's no guarantee they'll be able to sell their catch.
He feels the risk of wasting time, and money on fuel, is too great.
Mr Scott told Representing Border Brexit was making his business "unviable", and he said the fishing industry had been "sold out" by the UK Government.
Westminister did secure a Brexit deal, avoiding potentially crippling seafood tariffs. However, the problem now is the mountain of paperwork between that fresh tariff-free produce and the plates of European diners.