"This posts slider" not functioning

I have setup sliders before using the options under a post and then specifying “this posts slider.” However, there is no longer a way to add a slider to a specific post. The block to do this has disappeared. I can click on insert slider, and then I can click on “This posts slider,” but without a way to configure “this posts slider” it is useless.

https://ww.wp.xz.cn/plugins/soliloquy-lite/