Hi~ tiled map layer disappear when zoom deeper

[ccyeh0901]

Hi~ I built my own xyz tiled layer and replaced the OSM layer with it, all is fine, but when zooming deeper, the tiled layer disappear, how can I let it still show when zooming in? Could you give some suggestions on this, Thanks in advance, We'd like to build a indoor exhibition booth map, so we need more detail when zooming in :)