Adding Spells

I can not add the 5e version of a spell that exists in 5.5 to one of my players spell lists. I have checked off 5.5 on the sources, and any spell that was available in 5e but is now also available in 5.5 is unable to be selected. Is this intended?  

Quote from About_42_Bears >>

I can not add the 5e version of a spell that exists in 5.5 to one of my players spell lists. I have checked off 5.5 on the sources, and any spell that was available in 5e but is now also available in 5.5 is unable to be selected. Is this intended?  

 Is the character built as a 5.5e character? Older versions of spells (such as Cure Wounds) don't have new versions of classes added as compatible, with the only exceptions being spells like Vortex Warp where the update came later than the PHB.

And yes, this is intended. If any part of 5.5e is used in a campaign , everything that can be updated is meant to be for everyone in the campaign.

Quote from About_42_Bears >>

I can not add the 5e version of a spell that exists in 5.5 to one of my players spell lists. I have checked off 5.5 on the sources, and any spell that was available in 5e but is now also available in 5.5 is unable to be selected. Is this intended?  

To answer your literal question: yes, it's intended. The official rules say that if you're playing under the 5.5e rules, you're not meant to be using the 5e versions of spells (and other things) that have been updated for 5.5e, so D&D Beyond doesn't allow such spells to be used on characters using 5.5e classes.

If you're playing under the 5e rules, you can still use the old stuff, but you would need to actually select the 5e version of the class instead.