Can't drag a clip on its own when the timeline has two lines of clips

Hi guys

can I please get some help on how to detach two lines of clips from each other?

I started editing my video and needed to use different footage to run at the same time. One for audio only and the other for image.

I changed my mind about the order of clips on one of the image-clips and was going to drag it to a different position but the audio-clip was is coming attached every time.

How do I stop this from happening?

Thank you!