How do I get rid of volume bar on screen edge and back on top

[mustang7757]

Please anyone can help me about this! I just use a volume then this panel cant disappear.
Im sorry for grammar
(Galaxy A12)

Hi, welcome to AC!
You try Sound Assistant app from Galaxy store?

 

[B. Diddy]

Welcome to Android Central! Are you saying that after adjusting the volume, the volume slider just stays on the screen forever? Have you noticed any problem with adjusting the volume using the buttons? I'm wondering if one of the buttons might be stuck.