Toilet Installation issues

I just finished tiling my bathroom (remodel) and made an attempt to reinstall the toilet. The flange is approx 1.5" below the surface of the tile. I thought that if I installed an extra thick wax ring I'd be fine, but it wasn't thick enough. I didn't feel resistance when I set the toilet. Upon inspection, the wax ring didn't compress at all.

I've read that you can double the wax ring. In this case I would purchase a standard ring that would go on top of the extra thick ring (w/ plastic funnel pointing down).

I've also read about adding a flange spacer and then just using one ring.

I would really appreciate any thoughts on the matter.

Thanks

1.5" is too low for wax.
You will have to raise the flange.

Considering that the flange is supposed to be on TOP of the FINISHED floor, you goofed! How easy it is to fix will depend on what's underneath and what access you have to it.

Ok, so I actually measred and was way off the first time. The distance from the flange to the top of the finished floor (tile) is only 7/8". Does this still warrant raising the flange? Other options? (2 wax rings, spacer, other?)

That is too low even for a jumbo wax ring. I prefer a couple of extension spacers, as opposed to double wax, although the latter has been successfully used by probably thousands of installers.

See if two wax rings will compress.
If you don't feel compression, then you will need something else.

The wax is placed on the floor flange, not the bowl.