Thanks for your question.
Are you actually still employed by the employer?
If you are not:-
You need to be aware of the time limits. If you wish to recover them by an application to an employment tribunal then you must issue a claim there within three months from the date the money was first unpaid. If you are already over this time limit then you will have to issue a claim at the County Court for the money, if the amount owed is less than £5, 000.00 you can issue a claim for it yourself via www.moneyclaim.gov.uk. It's fairly straight forward and easy to use.
In the first instance I would try and get an informal/pleasant acknowledgement from him that he owes you the money. Perhaps an informal "Hi, the cheques you gave me for the money that bounced? Can you send me another one for the amount outstanding please. Thanks". Any affrimative response from him will constitute an acknowledgement of the debt.
Then write a formal letter to him and send it by registered post. Outline the money owed and state that you require payment within 7 days of the date of this letter failing which you will issue a claim for the money either at County Court/Employment tribunal.
If he does not pay the money then you will have to issue a claim. It would be helpful, but not crucial, to have a copy of your employment contract (if any) and you will need to explain in a witness statement how the situation arose and to which period of paid work it related.
Again, please specify if you are still employed by the employed.
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