Welcome, gojennyfer, to Apple Support Communities!
We see that you have purchased a new MacBook Pro 2020 (congratulations) that came with iWork Apps preinstalled.
We further see that when trying to update one or more of those preinstalled Apps, you were presented with an error message about such being “refunded or purchased with a different Apple ID”.
We should be able to help with this.
The preinstalled Apps need to be “Adopted” by you, so they become associated with your Apple ID.
We have been seeing two, somewhat related issues in this regard.
- The Mac App Store (MAS) often doesn’t make it clear when you are not explicitly logged in. Go to the menu under Store -> View My Account. This should cause the MAS to ask for your Apple ID and password, so you can be certain you are fully logged in.
- When people use the Migration Assistant, to migrate their Apps to the new machine, any of their older versions of the preinstalled Apps will sort of “interfere” with “Adopting” the preinstalled Apps.
Once you have made certain you have explicitly logged into the MAS (1. above), you should, at some point, while navigating the MAS, looking for updates, or checking on the iWork apps (I’m sorry I don’t recall when, from my experience) you should be presented with a dialogue informing you that you have Apps that need to be “Adopted”.
See Get updates for preinstalled apps on Mac - Apple Support
Simply accept the “Adoption” of those Apps.
At that point, they become yours, and you’ll be able to update them as usual.
If the “Adoption” fails, then you may be in scenario 2., above.
In this case, the workaround seems to be to completely delete the App in question (making sure you empty the Trash, perhaps even rebooting, afterward, to make sure the OS doesn’t “remember” the “offending” App). Then locating the desired App in the MAS and installing it.
Fortunately, this is not a problem for Free Apps like the iWork Apps.
(For those that ordered machines with Premium Apps preinstalled, this can be quite problematic.)
Please let us know if this helps, or if you need any further assistance!