Watch the report by Work and Economy Correspondent Carole Green
It has been a month since the Brexit transition period came to an end.
Despite plans being put in place to cope with large traffic queues at Welsh ports, the number of lorries passing through has dropped significantly.
Stena Line - which operates the Port of Holyhead on Anglesey - said it is seeing half the number of lorries passing through compared to this time last year.
It also said 60% less freight is passing through the Port of Fishguard in Pembrokeshire.
So, how has Brexit changed Welsh ports and why?
The alternative routes and why they're preferable
Since Brexit, hauliers are choosing alternative routes to the continent due to differences in paperwork.
Many lorries are now travelling directly from Dublin, or going via Belfast to ports in north west England and Scotland.
It means Stena Line is reducing its services and capacity in Holyhead, with one of its biggest ferries being redirected to Cherbourg in France.
Simon Palmer, from Stena Line, said: "While we're seeing lower levels [in Wales], we are seeing higher levels going via Belfast because it's unfettered access to Britain, and we are seeing increased levels going directly to the continent."
One Irish lorry driver who was passing through Holyhead told ITV News he was held up in Hull, and was concerned he wouldn't make the boat.
But Stena Line, which recorded record losses last year, owns Holyhead Port so will want to see business back at the UK's second busiest roll-on-roll-off freight port.
What is groupage and what is its impact?
Groupage refers to freight transporting various goods from several different companies in the same load.
It enables businesses to make the most of lorry space - if one customer does not have a full truckload of goods, their cargo can be combined with another customer's stock.
But it now requires each product to have its own code, which can be complicated, time-consuming and costly.
Many lorries travelling through Welsh ports will be carrying hundreds of different products.
"Before you could be in and out and you were gone. Now it's slower and more difficult," another Irish lorry driver said.
"You can't just turn up regularly and get a boat now. You're curtailed to your numbers and getting your clearance and all that."
What about the businesses themselves?
David Lambert, a wine merchant in Bridgend, said it is now quicker for him to import from South Africa than France.
He said he has stock stuck on the continent and supplies are running low.
"Now, post-Brexit, we have to spend quite a while getting not only the purchase order correct, we have to change the purchase order now to have the box type, the size of the box, we have to specify how many litres are coming across.
"You could have up to six pieces of paperwork where previously there would have been just one."
Will the drop in freight be permanent?
Stena Line said the Holyhead land bridge is the most direct, quickest and cheapest route in and out of Europe and is confident trade volumes will return.
"We are hearing from hauliers - the land bridge is still their number one choice, and it will always be the quickest and most cost-effective route for Irish hauliers to come through Holyhead to go to the continent," Mr Palmer said.
He added: "It would help if there was coordination between the UK, Irish and Welsh governments, just to talk through some of the issues hauliers are having, and to try and work with the sector to make things easier for them."
Virginia Crosbie, Conservative MP for Anglesey, said: "I don't want to say that these are teething problems. These are real concerns that we need to work together to get solutions for.
"I want to make sure that I've got happy traders, happy hauliers and happy ferry operators to make sure that we've got the systems in place.
"But I firmly believe that the situation we have at the moment is a temporary one."
A UK Government spokesperson said: "Freight levels across all UK ports, not just Welsh ports, have been lower as anticipated at the beginning of this year, but flows are steadily increasing and we expect this to continue in the coming weeks.
"We are confident that Holyhead and the other Welsh ports will continue to thrive. The best days are ahead as we build on the opportunities of being an independent trading nation."
Analysis from ITV Wales Work and Economy Correspondent Carole Green
Stena Line has moved one of its biggest ships off the Dublin to Holyhead route and transferred it to sail between Dublin and Cherbourg.
The number of services each week across the Irish Sea have also been cut. Freight is down and capacity cut.
As ever, it's a mix of factors coming together: Brexit paperwork, pre-Christmas stockpiling and winter lockdown.
Businesses want to know their goods wont be held up at borders. That border between the UK and EU is now at Wales' western facing sea ports - not just Holyhead, but Fishguard too.
The anticipated queues of lorries haven't materialised and only a tiny percentage of trucks are being turned away with paperwork problems.
However businesses looking for certainty are choosing to ship direct to France - at least for now.
Pre-Christmas trade in and out of Holyhead broke records with seven weeks of stockpiling ahead of the end of the Brexit transition period.
The Covid lockdown also means non-essential retail is not being shipped right now, which could account for 25% of the downturn.
The Irish Government has announced that goods shipments doubled with France and halved with Britain in the first month of post-Brexit trade.
And Holyhead Port is being hit twice over. It has built its business fifty-fifty between freight and passengers.
Right now, more freight business is heading direct to France and tourists are grounded.
There is one possible major change on the horizon - a bid is currently being prepared to apply for Free Port status. If awarded, customs and paperwork would be simplified giving a boost to enterprise and trade.