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Is there a deadline or we can surrender anytime?
If you don't renew it within 3 years, there will be a fine. Additionally, using it for travel may incur extra penalties.
However, these rules and fine amounts are often enforced at the discretion of consulate officials and are not always clearly stated.
Even when they are mentioned, the links provided are usually outdated.
If you contact BLS, you'll get a different response each time. It's best to take care of it as soon as possible.