Error -23 iTunes/iPhone since updating to Mojave

Ever since I updated to Mojave, I have not been able to update my phone via USB connection with my MacBook Pro. When I connect my phone, it syncs with iTunes just fine, but when it asks me if I want to Download and Update and I say yes, it errors out on the download. Error -23.

I've read Apple's support page https://support.apple.com/en-us/HT204770 and looked through old forum topics, and they indicate it might be a security or hardware issue.

...But it was fine until I updated my computer to Mojave so I'm skeptical that it has anything to do with hardware.

I have an iPhone 8 on 12.1, and a MacBook Pro (2017?) on 10.14.2. (I just updated to 10.14.2 because the previous version wasn't working and I hoped the update would.)

Any ideas?

I know I can update the phone via the phone (that's what I've had to do for the past 3 months) but it takes at least twice as long. ...And I'm disturbed that it's not working via iTunes.

Thanks!

(Oh and I have not yet tried to restore. ...Please don't make me do that :( )