Project 3 beginers' kit (love o meter) light don't light up with good intensity

Hello everyone

I'm into Arduino for 4 days goes quite fast as I have some programming background but I have an odd problem with the "love o meter" project.

In this projects lights are meant to light up depending on teperature mesurement with a sensor. They light correctly but with an incredibly low intensity.
The resistor I put is the one specified. I also tried without it....but it doesnt change anything

The led is good...I played project 2 which has an output in common and the physical mounting works right.

I ting my arduino doesnt send a 5 volt signal...or a delay messes with something...but I don't succeed with finding the source of the problem.

Someone familiar with this project has any idea

Thank you very much


solution found