voicemail drops

Hey guys. are there any apps, online services etc that allow you to do voicemail drops for free? Don't even need a service, just a way to do it manually would help already!

Hi guys, Wondering if anyone has knowledge with ringless voicemail drops. My Situation: A competitor of mine has it set to when you sign-up for a free report on his website, you get sent a pre-recorded "phone call" that goes straight into your phone's voicemail. This message was sent the second...