Reason: Glue was not applied properly when decorating the panel, or the glue used was unqualified. It may also be that the moisture content of the material is too high and the site is too dry now.

Remedy: Take the door down and level it, cut off the wood skin with a wallpaper knife, and carefully put glue into it (splicing glue and white latex are acceptable, unqualified or fermented glue is not allowed). If it is completely tilted, put it straight. Then wipe off the residual glue with a wet cloth and press the same flat thing, and it will be ready in four hours (the curing period of glue must exceed four hours).