Ok, so the bug starts after you are done with Default mode. If you go into a tower on any other mode, it will appear that you are starting the tower in the mode required. In this picture, it appears the tower with be on Apocalypse.



However, when you actually start the tower, you will see the Default difficulty logo in the top right:



This means that your tower will be a Default tower. Here is how I fixed mine.

You started a Default tower when you wanted and selected Adventure or Apocalypse.. That's ok! Thats actually a part of how we are going to fix it. First, once you load in, you are going to leave the tower.



Now that we are back to the campsite, go back to the tower selection and Give Up on your current run.



...No worries, this isn't the tower we want anyway.

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You can see we still have Apocalypse toggled here too. Now we start a new run!



vvvvvv



Here we are! We see that the logo in the top right is the Apocalypse difficulty logo! Let's do an Apocalypse tower run!

That's a simple guide on how I got around this bug. I hope this helps someone, and please feel free to comment below if you found something else that helped you!
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