AliExpress sent me an email saying the product I'd bought is illegal

So today I got this email from AliExpress:

We hope this message finds you well. Your satisfaction is of the utmost importance to us, and we strive to ensure that the products available on our platform meet corresponding standards. We have identified a potential non-compliance issue with a recent product you have purchased. Product Name:"......" Cause for the potential problem:Illegal Product We take your safety and satisfaction very seriously, and we want to bring this matter to your attention promptly to ensure your shopping experience with us is in compliance with applicable laws and your expectations. You may contact the seller in order to find more information and in case that the product is actually illegal, negotiate a solution such as requesting the return address of the seller and returning the product to the seller. If however there is actually no issue with the product, please disregard this message. If you have any concerns about the product or have any further related questions, you shall contact the seller directly. We regret any inconvenience this may cause. Thank you for choosing AliExpress, we are here to assist you every step of the way.

I contacted the seller asking what exactly was the issue, they replied and easily approved the refund, but did not answer the question.

Additionally, the product's page now states "the product is not available in your country"

Has anybody faced this? Do you know why exactlu a product is illegal and when does AliExpress send emails like this?