This may help
https://vborg.vbsupport.ru/showthread.php?t=265141 but there's plenty of anti spam/bot mods out there make good use of them and your troubles will be pretty much over. As for waiting for a moderator from here to login to your site, you may have a long wait as thats not their job, settings are things that you set specifically for your forum, someone else setting them may not be how you want your forum to respond.
Your best bet would be to tell us which settings in admincp>vBulletin settings>User registration options you have set ....etc then we can tell you what, in general, we have ours set to.