It turned out it was a problem with the breadboard. Once I soldered the components on the PCB that I designed, the problem disappeared. It must have been a short or flimsy contact on the breadboard. Sorry for bothering you again. Thank you to everybody for bearing with me.

 

As a thank you to everybody here are some photos of the final product:
<link removed>

Please post the photos here. The link you provided required access to all photos on my phone and Bluetooth on my phone.

No thanks.

When you’re posting, use the “Attach files” button to upload your photos.

 

Sorry. I removed the post. If you remove the link in your post nobody else is going to be affected.