Do not use Coinbase! They have extremely poor service and will not support you if you ever encounter issues logging in. Instead, they will write a generic response to your ticket and immediately close it. If any major bank tried to pull this they would get buried in lawsuits.
Again, avoid this service at all costs. Forget their greedy 5% fees on deposits/withdrawals - it doesn't even matter if you can't get your BTC or USD back period. That's a 100% fee.
Is that happened to some people? I can't believe this kind of bad news because as far as I know, coinbase is highly trustable company to store cryptoasset or to trade them. However, this kind of issue will give a bad impact on their platform and decrease their reputations if many people report this and take legal action. Do you think this can be categorized as scam?