Two months later the local authority received an anonymous phone call reporting that the premises had been vacated and put up for sale.
The information prompted the council to make further enquiries.
The premises were visited and an estate agent's board was on the building.
The estate agent was contacted and their records showed the building had been vacant since February 2020.
Details of the investigation were revealed in a report by the Local Government Ombudsman.
The report states: "The Council said this prompted it to make further enquiries as there is no entitlement to small business rate relief or the Small Business Grant if the premises are unoccupied.
"An officer visited the premises and found the roller shutters on the windows and door were closed. The Council says this prompted it to ask (the owner) to provide evidence to show she was still trading.
"In response to the Council’s requests for further information the owner's son emailed the Council in August 2020.
"He attached photographs of what he called delivery notes. He also said they were in the process of selling the shop and that his mother is opening the shop intermittently.
"He said the stock was being run down and trade was only about £30/40 a week."
The report continues: "The Council says it was not satisfied with the evidence provided.
"It says one invoice related to another business in the area but did not include the necessary VAT registration number and so it had concerns about its validity."
The Council also contacted a wholesaler in respect of another submitted invoice.
The wholesaler rang the Council in October 2020 and advised that while the stationary was genuine, the date on it was a Sunday and its agents do not work at weekends.
The wholesaler said the name and signature were not that of its local agent.
The report added: "It said the costs for the different confectionery items are not the correct values for the products. It also told the Council that the tracking device on the local agent’s vehicle was checked and showed he was not near the shop premises on that date.
"The wholesaler also said the serial number on the document was far removed from the sequence of receipts used by the local agent in 2020.
"It said while it previously supplied the shop, its last visit was in 2019."
The Council said items on two of the invoices provided were not items that a convenience store would normally buy for resale purposes.
The invoices showed purchases of two director chairs, a single bottle of shower gel, a single bag of pulses, a table, a gazebo and a shower head.
The Council said this evidence did not persuade it the shop was occupied and trading both on and after March 11, 2020.
Officers then asked for extracts of the shop’s sales/purchase ledger and bank statements for the business account.
The owner's son did not provide any bank statements.
He instead provided copies of handwritten sheets showing the weekly amounts taken.
The owner's son complained to the Ombudsman that the request for repayment of the Small Business Grant was based on "incorrect information."
He also claimed repayment of the grant would cause significant financial hardship.
The complaint was not upheld by the Ombudsman who found that there was "no evidence of fault" by the Council.
The report concludes: "I am satisfied the Council has considered all relevant information and has given clear reasons for its decision.
"The Council’s investigation concluded that on March 11 the premises were not occupied and being used by (the owner) to conduct her business.
"It therefore decided she was not entitled to the small business rate relief or the Small Business Grant."
The location of the shop and the name of the business owner is not stated in the report.