Have you tried using a different phone number? If you do so and still not worked, I think the problem is on their site.
Yes, most of them are ponzis ( like Hashocean, Bitsrapid etc. ). I am also very cautious with them. I deposited a really small amount in bw.com just to compare the profits to Hashnest ( operated by Bitmain - this is the only CM provider I trust right now ), before I move in with bigger funds. I don't think BW.com is a scam, it just has crappy customer support.
But at least you know the risk right? Yes, it's really awesome that you just wait and then earn, but the risk is always there. Anytime they can be scam even you trust them the most. HashOcean last for a long time, but what happened? They also turned to scam. I do invest in them also and luckily I got my ROI. Well, this time in your situation, it's still your decision since it's your money
We are just stating our opinion and just some reminder about cloud mining sites.