Only One String Lights Up

I’ve just taken delivery of a box of the 150ft Lepro E1 AI LED Permanent Outdoor lights. There are 6 strings lights in the box with a Controller device and and a Power Supply cable. I find when testing the lights that only the  string light connected to the power supply cable lights up. The string connected to the first string light does not light up; nor does the the third, the fourth, the fifth or the sixth. 

I’ve swapped the light strings around so that a different light string is connected to the power supply cable. On each occassion, the string connected to the supply cable lights up while every other string in the chain show no sign of power supply reaching it.
I’ve downloaded and installed the Lepro app, updated firmware, comnected to wifi and added the string connected to the power supply to the app but I’m stuck with this issue. I actually bought two boxes of the Lepro 150ft e1 and I’m considering sending them back but first, I would appreciate the community’s best advice for resolving this issue. 
Thank you. 

Dear user,
Thank you for your message.
Please select the device, access the DIY interface(the bulb icon) and then refresh "Length" in the upper right corner.
Here is a video of how to set up and app functions for your reference: https://www.amazon.com/vdp/09fef38d8fb6463dbe9b5708880eabbd?ref=dp_vse_ibvc1 
Please feel free to contact us if there are any other questions.
Best regards
Lepro Customer Service Team 

@Lepro_CS_Taylor

Thanks for your reply. I’m unable to see the end of each line of the reply and I do not see a link to the setup video  you referenced. 

Dear user,
Thank you for your response. We are sorry for any inconvenience it caused.
Please select the device, access the DIY interface and then refresh 'Length' in the upper right corner.
 
https://www.amazon.com/vdp/09fef38d8fb6463dbe9b5708880eabbd?ref=dp_vse_ibvc1 
Please feel free to contact us if there are any other questions.
Best regards
Lepro Customer Service Team