I've been trading on Coinbase about 4 years. I sent a Litecoin back in April as a test before sending the rest, and it's still pending on the Coinbase end after 4 months. After several support tickets, and trying to call I gave up on them entirely. It shows up with over 60 thousand confirmations, and they just completely ignore me. I'm not the only one that's had this happen in recent months. They have quickly turned into the worst exchange available. I'd heavily advise against trading with them. If you have an account with them, move it somewhere else, or offline.
I've been making use of Coinbase for a long time, but stopped using it around July . I never had transaction issues with it, though I was only making bitcoin transaction, and never made/used a Litecoin or ETH on it. The login issues, I think that's due to their security system. For example; if you try to log into their mobile wallet, it says you should check your email and confirm it's you. So I think they're trying to protect their users. But I already stopped using Coinbase, I'm now sticking to Xapo and Blockchain.info.