First of all, we have to know why Yocan B-smart occur Flashing Light error.
When it flashing 3 times, means your device short-circuit error.
And when it flashing 5 times means it's not detect your cartridges.
Here are some vape track tips:
1. Try to use q-tip clean the contact point with Isopropyl Alcohol.
2. Pull out the contact point bottom of the coil. Sometimes the contact point cant connect when you installed.
3. Soak the coil in Isopropyl Alcohol. But please DRY it when you re-install it.
4. Try to install a brand new coil.
5. Contact the shop you bought it from, ask the sales guy to help you check and fix this problem.
6. Contact Yocan Tech, fill out on www.yocantech.com/contact