Pressuming it is a plaster wall you have gone into? First step would be getting bigger rubber grips so tight you have to really squeeze them in. Too late to use an authentic gyproack screw lol
But plaster will often wiggle and loosen over use. In my family, we do dodgy DIY repairs, that are perhaps not what builders/handymen would do,so bour next step would be to get butterfly screw anchors and a bit of glue and lodge it into the hole (making sure it is a tight fit, wait a day for it to dry and then screw the holder on.
The butterflys can be pretty handy, can put them in straight, but when you start screwing they open up and lie flat against the wall, anchoring in the hook. The glue tries to keep it from wiggling. Only issues is to check whether the screw will fit through and not hit the opposite wall, and that the rack sits well over the anchor.
pic:
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