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You only have rights against dismissal if you have continues service as an employee. Neither agency workers, nor the self employed are employees. So if you are not an employee you have no protection against unfair dismissal. This means that the employer can dismiss you at any time and for more or less any reason. In the case of self employed workers like you, all that is required is that they pay you any termination notice you are entitled to under contact. Your service history with them does not matter unfortunately. As there is no unfair dismissal protection they can just rely on the contractual termination clause, which in this case is 5 days. The fact that the contract is not signed by you does not change your rights to be honest. You still do not have the protection you are after. The only thing is that there will be no specific notice period for termination and instead ‘a reasonable notice period’ will be implied, which could be the same or slightly different to the one you already have in place. I'm sorry if this is not necessarily the answer you were hoping for, however I do have a duty to be honest and explain the law as it actually stands. This does mean delivering bad news from time to time. I hope you understand and would be happy to provide any further clarification if needed. If you are still satisfied with the level of service you have received I would be grateful if you could please take a second to leave a positive rating by selecting 3, 4 or 5 starts at the top of the page. Thank you

You are welcome all the best