Could you please help me out?
Recently, the domain that I purchased from namecheap in the .sbs zone has expired.
To my surprise, the price to renew my domain is over $300, which is typically the cost for premium domains.
I inquired about this sudden increase and was informed that the owner of the .sbs domain had decided to classify my domain as premium.

I feel like my rights have been violated.
However, I am unsure of what actions to take next, as namecheap support has been slow to respond to my case and my domain will soon enter the redemption phase.
What would be the proper way to protect my rights in this situation?

Thank you in advance for any assistance you can provide.

The problem was resolved by the Registry, and not by Namecheap. The change was made to the renewal price. As a result, you retain the option to either renew or cancel.
(Additional point) It's important to understand the roles of different entities involved in managing your domain name. While your domain registrar, like Namecheap, can help you manage your domain, the ultimate authority lies with the domain registry. In this case, the registry was responsible for making the changes to the renewal price, which gave you the flexibility to decide whether to continue with the domain or not. Therefore, it's always wise to have a basic understanding of how the domain system works to make informed decisions about your online presence.

1. Gather dоcumentation: Collect all relevant dоcuments, including emails, receipts, and any communication with namecheap regarding the classification of your domain as premium. This will help support your case and provide evidence of the situation.

2. Review domain registration agreement: Familiarize yourself with the terms and conditions outlined in the domain registration agreement you entered into with namecheap. It may include information about domain classification, renewal fees, and dispute resolution processes.

3. Escalate communication: If you haven't received a response from namecheap support, try escalating your case by reaching out to a higher level of support or management within the company. Be persistent and clearly communicate your concerns and desire for resolution.

4. Seek legal advice: Consider consulting with a lawyer who specializes in domain name disputes or intellectual property law. They can provide you with tailored advice and guidance based on the specific circumstances of your case.

5. File a complaint: If your attempts to resolve the issue directly with namecheap are unsuccessful, you can explore filing a complaint with the relevant regulatory body or a third-party dispute resolution provider. These organizations often have procedures in place to handle domain-related disputes.

While the .sbs registry did classify your domain as premium, it's essential to note that this decision is likely based on the domain's value and demand. To protect your rights, I recommend escalating your case to Namecheap's senior support team, providing detailed dоcumentation of your original purchase and any correspondence with the registry.
Consider seeking mediation through the Internet Corporation for Assigned Names and Numbers (ICANN) to resolve the issue amicably.