PixelSpark Server is starting but then stopping imediately afterwards.

To whom it may concern,
I am having trouble playing PixelSpark with my friend we launch the server with PixelSpark from technic as the mod-pack option. We each have technic downloaded to its most recent version and we have attempted to run the server multiple times. The version on Aternos says 2.4x but I believe that our version of PixelSpark is 5.1.5 this is an issue that I can not fix because I do not know how to change mod versions on the newer layout of Aternos. I apologize for any inconvenience this may have caused and thank you for not only Aternos but also your help.

They aren't the same. How do I make them the same? The mod itself is on the most recent version but The Aternos option on server config is different as said above.

Ok both versions are marked as 2.4x I will try to run the server