Adhesive surface that requires maintenance

The product is cheap (10), it does the job, namely Qi recharge a compatible phone (LG Nexus 5 for example), but wobbly no use actually. I do not see the point of having a phone leaning.
The circular white part is supposed to hold the phone with an adhesive effect. Unfortunately this adhesive effect does not last, it must be regularly wet (slightly) this part and the phone can again hold, if it slips.
It should also position the phone (neither too high nor too low) for the charging function.

Prefer XCSOURCE flat model, it is more expensive but more convenient.