In any of these cases the red status LED on the sensor lights up. The Sensor DS18B20 is connected to the Raspberry Pi 3 B+ to the 5v on the GPIO pins. Using the 3.3v pin makes the light of the sensor light up but does not show anything on the Pi. When connecting to the 5v pin the following happens.
When attaching a DS18B20 to my Raspberry Pi I usually see 3 ID's in my /sys/bus/w1/devices folder. after a little while 1 of these 3 disappear and the other 2 change name. The sensor is not readable because there is no "w1_slave" file in any of these folders. furthermore the ID's look nothing like anything else I see in tutorials or questions on the internet.
I have already gone back with the sensor to the shop I bought it from explaining the issue to them. They said they have never heard this before (I believe them) and they gave me a new one. The previous sensor would not show anything at all while connected to 3.3v on the Rapsberry Pi. I haven't tested the 5v on the old sensor because I came with the 5v idea after I received a new one
A thing to note about the sensor is that it is a tiny circuitboard with the resistor already properly connected.
Here are 2 Pictures of what the actual sensor looks like, the red LED is on in the picture but not visible because of the flash.
I have already searched the web for this problem but there is nothing like it. All the settings on the Pi seem fine, at least the ones other problems and tutorials talk about (the dtoverlay=w1–gpio setting has been set correctly for example).