LED strip suddenly starts to flash?

I was at the Poco today and bought a 3m strip light.
At first all well and good, but for about an hour there are always problems. First, the light flickered funny, then it flashed suddenly only red and very weak, as it has caught again briefly, the colors were darker and different.

Tried at the socket, which seemed to other electrical appliances but in order, laptop loads as usual, lights go etc. The light strip itself had no problems with other sockets and also here it is briefly here and there.
Is the tape broken or is there a solution I just overlook?

The product:

https://www.poco.de/506908900/led-lichtband-mit-farbwechsel-leds-laenge-3-m

Well. It's just from poco.

Something not properly put together?

PS: "poco" is Spanish and stands for "little". And that writes the quality of the products sold there quite well. Had bought 3x and a exchange rate of 100%. I have not bought anything since then.

That sounds like a broken controller. So the LEDs themselves still go, only the box in front of them that does the color control has probably not survived. Are there any synonymous individually on ebay.