Independent retailers have complained of cramped storage rooms and incidents of verbal abuse after Evri failed to pick up parcels from stores for several days.

Better Retailing understands the issues began just before Christmas, intensified by Royal Mail strikes, but have yet to be resolved despite disruption ending.

Natalie Lightfoot, owner of Londis Solo Convenience in Baillieston, Glasgow, revealed at one stage she was left with nearly 500 parcels for four days.

“It was a total nightmare,” she said. “I understand the postal strikes caused issues over Christmas, but drivers have been failing to visit us on their routes in the past few weeks.

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“I’m a small store and don’t have a huge amount of storage space. My stock room was full, and I couldn’t use it for anything else.”

Lightfoot said on one day in particular, a driver told her they didn’t have any room, and never returned. “We do ring the helpline, but they aren’t able to give you a huge amount of accurate tracking information.”

She added: “A lot of customers understand, but we are faced with trickier people who think that it’s our fault their parcel hasn’t been picked up, which is really frustrating.”

Several others confirmed to Better Retailing they had experienced something similar in recent weeks.

A spokesperson for Evri said: “We can confirm that we have been in contact with the shop owner, Martin Lightfoot [Lightfoot’s husband] and are investigating his concerns. He has confirmed he has already seen an improvement.”