ws2812b Light Strip & Arduino Not Working

I want to preface this by saying that I don't know much about how circuits or soldering or programming works at all. I've tried to myself all through various forms and youtube videos, but this is my first post here.

Right before summer, I bought an Arduino starter kit, a sparkfun spectrum board, and a ws2812b light strip with 300 leds on it. I followed a guide from callmekoko on youtube and github. I was able to solder the boards together, upload the code to the arduino, and I bought 2x 12v 2a 24w power supplies.

I hooked up one power supply to the light strip, and I plugged one into the arduino. I took the red, green, and white cables from the light strip, and made the appropriate connections with them on the board.

When plugging my phone in to play music, I was able to get the lights working and they flashes with music.
I ended up losing one of the power cables, so I let the whole thing sit over the summer until now, when I ordered another power supply of the same kind from Amazon.

I am now using the same set up that I was before, but when I power on the light strip, there are two different things happening. For one, the first 6 to 10 lights on strip will briefly light up, and then they will also blink with an incredibly dim blue light every few seconds.

Secondly, sometimes, none of the lights will turn on except for the 3rd light and the tenth light. One of them will stay a solid orange color, and one will stay a solid green color. Nothing else will happen, even when I make the connection of the light strip to the board.

I am not really sure what my issue is here, so I was hoping somebody could give me some ideas.
If you have any questions at all, let me know. I am sorry if this is confusing.

Thanks!

OK, now, you said WS2812 strips. These require a 5 V power supply, not a 12 V. Or do you have a different sort of LED Strip?

Similarly, you need a 5 V power supply - which can be the same one as for the LED strip - to power the Arduino. The regulator on the Arduino can barely power the Arduino (UNO) itself if fed with 12 V, and it is wise to simply avoid connecting it to 12 V via the "barrel jack" or "Vin" and always power it from a 5 V supply, possibly via the USB jack or the "5V" pin and ground.

So what is the story?

I followed a guide from callmekoko on youtube and github.

When you say such a thing you need to post links to what you have seen. Even if we searched for these terms we still wouldn't know we were seeing the same thing as you.
A photograph of your setup would be good as well.

Please read this:-
How to use this forum
It tells you what you need to provide when you ask a question here.

Ah well maybe its all in the power supply. For some reason, I never used 5v and just assumed that 12v would work. That's what I did use at first and it worked fine so maybe the light strip burned out. I will try to take a small video of the strip and what its doing.

I am also ordering an a to b usb cable that I'll use to power the arduino instead of another power supply.

The youtube vid I followed: https://youtu.be/Af74A0Tx-wA

The github page I followed: GitHub - justcallmekoko/Arduino-FastLED-Music-Visualizer: An Arduino based music visualizer using the FastLED library and a strip of individually addressable LEDs

For some reason, I never used 5v and just assumed that 12v would work. That's what I did use at first and it worked fine so maybe the light strip burned out.

I have great difficulty in believing that it worked with 12V.
Where did you put this voltage?

Do you not find the information density in You Tube videos lighter than hydrogen?
That git hub page is appalling too, what an idiot.

I will try to take a small video of the strip and what its doing.

It is much better if you draw a schematic of what you have, along with a photograph of your setup. Then post the code you are using.

So far we know essentially nothing about what parts you have.

You need to provide the Web links of the parts you purchased.

Yep, there's definitely a few appealing appalling things there!

Ok I have my light strip with the red and white power cables connected to a port that a dc power supply could plug into. I also have a red, white, and green cable on my led strip.

The red cable goes to the 5v, white cable goes to GNO, and green cable goes to the 6 as shown in the diagram above.

Those ports are all on my sparkfun spectrum shield which is soldered to the arduino. The arduino has the code from the github page on it.

Here are the links to the parts I used:

Power Supply:

Light Strip:

Sparkfun Spectrum Shield:

Arduino:

I'm just curious how to diagnose whether the issue is from the arduino contraption I made or the light strip itself at this point.