A company behind a record 146 million illegal calls about payment protection insurance has been fined £350,000.
People were left feeling harassed and threatened by the recorded - also known as automated - calls from Your Money Rights Ltd, based in Carmarthenshire.
The company broke the law by not having consent to contact people with automated marketing calls.
The Information Commissioner's Office issued the fine after an investigation.
It found the calls, made over four months, also broke the rules by not including the company's name and contact details in the recorded message.
The company was responsible for the most amount of automated calls to result in an ICO fine to date.
Steve Eckersley, ICO head of enforcement, said: "They are a blight on society that disregards people's right to have their wish for peace and quiet in their own home respected.
"We know people find calls playing recorded messages particularly intrusive because they are unable to speak to a call agent.
"Your Money Rights should have known that the law around automated calls is stricter than for other marketing calls."
Following the ICO's investigation, the directors of Your Money Rights Ltd, which is based in Ammanford but has its registered address in Darlington, are seeking to dissolve the company.
The ICO said it would be working to recover the fine alongside insolvency practitioners and the liquidator if the company moves to insolvency.
Mr Eckersley said the ICO's powers would be further strengthened when the UK government introduces a new law allowing it to fine the company directors behind nuisance call firms.
"If a firm goes out of business to try and duck an ICO fine then they're no longer making troublesome nuisance calls," he added.
"But the new law will increase the tools we have to go after them and hold them fully accountable for the harassment, annoyance and disruption they've caused."
PPI was designed to cover loan repayments if the policyholder fell ill or lost their job.
About 45 million policies were sold over 20 years from 1990.
But it became clear that it was mis-sold on an industrial scale to people who did not want or need it - or would not be eligible to claim on it - and have been able to claim for compensation.
The Financial Conduct Authority has set a deadline of 29 August, 2019, for the final PPI claims to be made.
John Mitchison of the Direct Marketing Association, that runs the Telephone Preference Service for the IPO, said: "We hope that in the future rogue marketers will face the real threat of prison when abusing consumers in this way, which will be an effective deterrent."