Is it okay to ask for hints during a system design interview?

I sometimes get stuck on a particular aspect during a system design interview, like ensuring exactly-once delivery in a distributed messaging system. When that happens, is it better to ask the interviewer for a hint, or should I propose a half-confident solution and then open it up for discussion? I don't want to come across as fishing for answers, but also don't want to get completely stuck. My usual strategy is to articulate the problem I'm facing and then suggest a few potential approaches, even if I'm not entirely confident in them, asking for their thoughts. For example, 'I'm thinking about how to handle duplicate messages here. We could use idempotent operations on the consumer side, or maybe a unique transaction ID. What are your thoughts on which approach would be more suitable for this specific context?' Is it always better to try to work through it yourself, even if it means some fumbling, or is a well-phrased question for guidance acceptable, especially if it shows you understand the difficulty of the problem?