If you're employer is doing something that you know is wrong, it can be a difficult decision whether to report it or not. If your employer is not responsive to your concerns, you may be worried about damaging your working relationship, or even being penalised at work for speaking up.
Employees who become 'whistleblowers' are protected under the Public Interest Disclosure Act 1998 (PIDA) from mistreatment by your employer.
If you believe you have been unfairly dismissed or treated unfairly at work because of disclosing any wrongdoing, you could have an employment claim.
A claim must be brought for unfair dismissal within three months of your employment ending. However, it's still sensible to seek legal advice even if this time has lapsed.