Recently got back into making accounts, and I've noticed that very routinely accounts will be logged out and locked because they are believe to have been "Stolen" immediately after finishing tutorial island. I use throwaway emails, so maybe that triggers this? Anyways, I reset the password and I'm fine, but I never experienced this in the past. More annoying than anything. 

If you're using proxies they could be bad proxies. If not, possibility your IP is flagged? I don't think jagex have any automation in place for account creations using random email address' as many others would experience the same issue. I think it's down to a proxy by the sounds of it. Or the possibility of the amount of accounts created within such a small timeframe

If you're using proxies then they're flagged. Or maybe a vpn or something

Ah,  yeah it must be the proxies then. Thanks all 

It seems to happen quite often when my workers make them. We just started to create them with Gmails and we give our clients both the email info and OSRS info.