Your ex-employer can ask whatever he likes but if he asks more than twice and you have already asked him to stop, that then becomes harassment which is a police matter. You are not under a duty to give a new address unless your contract says that you should in which case, if you don’t, you are just in breach of contract.
You say there was no contract between you in writing so there can be no agreement that you would give a forwarding address.
If you accepted that you owed this £5000, then it’s a different issue over whether the £5000 is in dispute. If for example he genuinely overpaid you over the last few months, to the tune of £5000 then there is no defence to keeping that money.
It seems however that you think he has paid you the correct amount of money and he thinks that he has paid you and incorrect amount of money and if that’s the case, then he’s going to have to take you to court and the judge will decide the askew.
Please don’t think that by not giving the employer your new address, you are off the hook. Your last known address is good enough for service of documents and unless your correspondence is redirected by Royal Mail, then you could end up with court proceedings and a County Court judgement at your old address, without even knowing about it.
. Can I clarify anything else for you?
I’m happy to answer any specific points arising from this.
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