Lidl has launched an investigation after a woman claims she was "taken to the backroom" and told off by a staff member for speaking negatively about the shop on Facebook.
Devon mum Ana Palmer says she was shocked by having her bags searched at the supermarket before Christmas and posted about it in the Tavistock Parish Facebook page.
"My shopping bags were searched in Lidl this evening," she wrote on December 22, PlymouthLive reports.
"I have NEVER in my whole life ever stolen anything!"
She went on: "I had a wonderful mum that had taught me a really nice thing in life which was 'If you can't afford it, save for it but if you really want it there & then, ask for it but never ever help yourself to someone else's things!'
"I didn't feel insulted by the fact that our bags were searched but just a little bit uncomfortable!
"The sales adviser told me that she had to do that because they've 'had a lot of mystery shoppers coming in recently'!
"Anyone else experienced this in Lidl recently?"
Romanian-born Ana, who works at Boots, says she regularly uses the local Facebook page for advice and didn't intend to target the Lidl worker who searched her bags.
"Most people were very supportive but there were certain individuals commenting in a negative way," she told the paper.
"I wanted to take it further, not to cause harm to the lady at her work but just to gain clarity as to why our bags were searched. I emailed Lidl and they haven't got back to me."
This week Ana says she was taken into a "backroom" and told not to complain about the shop's workers on social media.
"As I was shopping someone approached me out of the blue, didn't introduce himself, and said 'Hi, can you follow me into one of the backrooms so I can have a word with you?'" she claims.
"I panicked, I don't know why. I felt like I had to follow him, but later on, I regretted it. I know I could've said 'no I'm doing my shopping thank you very much'.
"So he took me to the back room and as we were walking I had a recording app on my phone and thought as a way of protecting myself and defending myself if anything happens I turned on the voice recorder."
The conversation, published in full on PlymouthLive, begins with the employee reminding Ana of Lidl's customer service phone number before saying she "chose to use social media to complain about an individual".
He added: "What you failed to do was mention to a member of staff or anyone about the issue."
Ana retaliated that what she posts on Facebook is her choice, to which the worker says: "I would ask you not to directly put abuse about a young woman on the shop floor who you upset by doing that."
He continued: "What I'm asking you to do is to not open abuse to staff who are working through this pandemic," before Ana said she would like to return to her shopping.
Speaking about the exchange, Ana said: "I felt absolutely dreadful. I drove home I was shaking, I spoke to my daughter [about it].
"I want her to learn from this rather than hiding what I'm feeling. It wasn't right and if anything like this happens to you, you need to email that company and find out why these things happen."
A spokesperson for Lidl said: "We were very sorry to hear of this incident and would like to sincerely apologise for any distress caused.
"We can confirm that this is currently being investigated by our regional management team and that our customer services team are in direct communication with the customer, who will inform them of the outcome."