I just tried to put down my oil based stain on my maple furniture top after using Seal Coat and nothing absorbed. Here was my process to get here:

-Sanded Maple top with 120 to remove scratches/smooth grain. Then 180 to smooth the grain a little bit more.

-Applied Seal Coat with a rag and let dry for 1 hour

-Sanded Seal Coat with a Maroon scrubbing pad (is this not enough sanding)?

-Applied Stain by brush very liberally and waited 5 minutes before wiping off w/ a clean rag.

Any suggestion on what I did wrong or how I can get the stain to take? Do I have to wait for the top to dry even before sanding even though no stain really penetrated (from the naked eye)?

that's an expected result.... stain is not going to take on a sealed surface....
What exactly are you trying to achieve?

Seal coat will work as a stain conditioner but you must thin it with 2 parts DNA to 1 part seal coat.
Sanding off the seal coat and them wiping the surface with dna is most likely your best option.

Hard or soft maple? Big box store stain? Why didn't you do this on a sample instead of experimenting on the finished work? First time you have stained maple? New to finishing?

If this is your first time staining maple, be prepared for some tweaking to your finish schedule. Maple is notorious for blotching, as most guys use some form of toning, to get an even application of color.
At this point, I would try to remove as much of the Seal Coat, if not all of it, and try a different approach ie., toning.

If you trying to seal for blotching,you need to do a wash coat
Usually thin out your sealer
Also scuffing pads are not ideally good for sanding sealer
220 grits would be better
Do a sample first!

You could possibly skip your stain coat all together. I’ve had success adding transtint dye to the Sealcoat. Then using a clear web over it.

Are you trying to use the Sealcoat to limit the penetration or blotchy effect of the stain? Are you using oil base or wb stain?

No harm here. Just sand off all the sealer coat. It's not hard to do, but just takes a lot of time.

Thanks for all the suggestions guys. Yes, I am pretty new to finishing, probably my 4th piece, but 1st Maple.

I used the Seal Coat to avoid blotches but did not thin it out with DNA. So, I sanded off and wipe down with DNA and a scrubby pad. I just applied my General Finishes on the raw wood sanded to 120 and it took really well. Now waiting to lay down a coat of shellac, before Poly.

Any tips or things to do different for finishing? I'm waiting the full 72 hours of drying since it is so humid in North Carolina.

Your flirting with disaster using 3 different finishes. Make sure to try that on scrap first!

How do you make money waiting for all that to dry? You should learn about professional finishes from an Industrial finish supplier and learn to spray. Stop using hobby crap!

If Dennis Schmidt was still on this site he would be telling you to use glue sizing.

Personally I would suggest trying the european waterbased stains from companies like ICA,Renner, Milesi etc.

They use premium quality pigments that are ground so finely that they act almost like a dye and give a much more consistent color than standard oil stains.