Thank you for the question. If you do not have a visa which allows you to work in the UK the employer is at risk if they employ you (or keep you employed after checks come back) if that job includes accommodation as part of the contract, then I am afraid that they can legally do this yes. If you have the right to work, but have been dismissed you could potentially take a breach of contract issue with them.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
https://www.lawsoc-ni.org/solicitors (N. Ireland)
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