Make sure the surface is clean and flat with no texture… then add a little moisture.

Thankyou every one for your answers
I now use a hook on back of door
I was getting stressed as I thought a suction cup would be perfect storage for Hairdryer.

make sure the surface is dry and clean to attach to. sometimes the actual quality of the suction cap isn’t that good

Give the back a clean. Then lick it! True.

Blu Tack may not work in a steamy damp atmosphere. You may need a hook that is more suitable for the weight and perhaps the width of what you are hanging.

Thankyou sooooo much everyone will try all your advice
The one I have is an everloc
It was given as gift but no instructions found.

I have one of these that I purchased from bunnings, I have a very heavy drier on it, and It is attached to Italian glossy tiles, they are new and I did not want to risk damaging them as the plumber cracked 2 and they were incredibly expensive, the brand I bought was everloc, it has a push and lock mechanism, and when it starts to release a little red line appears around the suction thing, this happens a long time before it releases, you then just remove it, clean behind it and put it back, they have a large range of products now and are more expensive than a lot of the suction cup products but worth every cent, check out the bunnings website and they have all the products on there, but they are called everloc. I cannot recommend them highly enough and if you are renting they are fantastic as you can take them with you, they are also well made and look good.

I have not had any success either also have a second toilet roll holder (it has screw knobs ) and it falls of the wall as well. Sorry about the pun : But I feel suction cups suck.

These plastic suction things are not very good. I would invest in a hook that you could use over your shower screen or on the back of your door. I use a over door hat and coat hooks are great as I hook on my hairdryer and curler and robe and extra towel.

I’ll also be watching this one to see any ideas. I’ve got an Ikea basket with suction cups for bath toys but one of the cups keeps coming loose!

I would think it should stay on. What about a huge amount of blu tack or double sided tape.