Inability to complete the employment process by a hospital. What to do?

Dear sir/madam,

I need advice or suggestion regarding my case.

I am a specialist doctor working in an MOH Govt job and I got a call from a private hospital in Dubai. CV was short-listed an interview was done and I was selected, then I received an e-offer letter and after accepting it, a final offer letter was signed.

They asked me to resign from my job which I did with 1 month's notice. Now after the cancellation of the license, they have to apply for a new license. For one month, I was waiting and asking for joining.

Out of sudden, they are saying that they are not able to obtain a license from MOH because this category of the previous license is not applicable to the private sector. From the start, I kept mentioning and asking to be sure; they said no issue will be for getting it. Now they said they can't.

Now, I don't know what can I do. I lost my previous job because of them.

I want to know what legal rights I have, and what legal action I can take against the new company.