It tells the recipient their movements have been monitored through their phone and they must pay a fine or face a more severe penalty, the Chartered Trading Standards Institute (CTSI) warned.
CTSI lead officer Katherine Hart said the number of Covid-19 related scams are growing by the day.
"I am appalled and infuriated at the ways unscrupulous individuals exploit this situation," she said.
"We see new scams daily, and I would urge people to seek advice before replying to any messages they receive.
"Anyone who receives this text should ignore it. It is simply another ruse to steal the payment details of users."
Ms Hart advised the public not to "click or tap on any links" in potential scam messages.
On Thursday, the Home Office granted police forces powers to order members of the public to go home or leave an area.
Officers can also order groups to disperse using "reasonable force", and can make arrests if someone refuses to comply.
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