Sounds like a tough issue.
Maybe there is a mechanism under which the new Saudi legislation allows you to receive profits which were made prior to the legislation coming into effect, when it was legal? I don’t know of the law in the country but you might need professional help here.
If this fails, remember that the money in your account is pf two types - deposited funds and profits. You could I hope argue with the Saudi authorities and your bank that withdrawing your deposit is not the proceeds of forex trading - the money was deposited with a company overseas and is now being withdrawn.
In any case, you must realise that when a company is asked to reimburse funds, whether deposit or profits they will be expected to make some enquiries as to how you obtained this money. They will need you to prove that it is money that belonged to you and to show how you got it. This is to protect themselves from a money-laundering accusation. If you can’t prove its your money, expect problems.
I hope you get what you are entitled to.