The actress, who plays Weatherfield's Eva Price, was given a reminder by show bosses after offering details of where she visits and shops, The Mirror claims.
Cast at the ITV1 soap are not allowed to endorse products and places on social networking sites. Last year, reports suggested that Helen Flanagan and Brooke Vincent (Rosie and Sophie Webster) had both been warned over promoting products online.
A Coronation Street spokesperson confirmed that the show's stars are told to be careful over what they tweet.
"We never get heavy with them, just a reminder to be careful," the representative explained. "We have a duty of care to make sure that they weren't inadvertently promoting products.
"There is no suggestion that any of the cast have been making money from it."
Tyldesley joined the cast of Coronation Street last year as show producers introduced the Price family to The Rovers.
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