Do you collect emails or now maybe cell numbers for SMS at an offline location? Then you might be experiencing bounce. Bounce is when the info you collected leads to a non-deliverable address.
This can be caused by illegible writing, wrong info heard, mistakes during transfer, etc. So how do you collect database information offline that is usable. You use online methods.
This may seem odd. After all, you are collecting the information offline. Studies have shown that using an incentive that is generated at the offline site can have a high conversion rate of customers that go online to fulfill.
This way you get your information accurately and electronically. Make sure you give an incentive that will encourage fulfillment and you can reduce the bounce.