A family-run florist says it is being besieged with up to 120 calls a day in a phone cloning scam.
Fraudsters posing as TalkTalk workers have switched their caller ID - the incoming number which appears on mobile phone screens - to that of The Flower Shop in Caversham, Reading.
The shop said "confused" callers asking for the telecoms firm had started contacting them on Friday.
The case is being assessed by the National Fraud Intelligence Bureau.
A TalkTalk spokesman said: "We can confirm that this incident is not related to TalkTalk."
Shop manager Denika Potter said some of those ringing the business had been abusive after the fraudsters had tried to dupe them into providing their bank details.
She said many people recognised they were being targeted by scammers, but mistakenly thought the call had originated from the florist.
"Most customers are nice, accept it and apologise," said Ms Potter.
"Some are very annoyed, which you obviously may be if you are getting lots of missed calls from a number."
She said the calls were "disturbing" her staff's daily work and added: "We are a small business and we're having to stop to answer the phone all the time."
An Action Fraud spokesman said it could take up to 28 days to determine whether there were "sufficient lines of enquiry for an investigation based in the UK".