More problems with my level 3 witch character.
Most of the character’s spells that have a saving throw are showing the correct DC, which is 19.
However, the Needle of Vengeance and Nudge Fate focus spells are both showing a DC for the save of 14.
This doesn’t matter too much with Nudge Fate since you’re only going to cast it on an ally who isn’t going to try to save against it anyway, but it definitely matters for Needle of Vengance which you’d cast on an enemy.
If I click “View spell” for NoV, it shows me it’s calculating the DC thus:
+10 Base Value (Saving Throw)
+4 Intelligence Modifier
+0 Novalue Proficiency Bonus (Untrained)
Of course a Witch is trained for this spell. For some reason the character sheet is calculating the prof bonus for some spells and not others.
Thanks for reporting this! Would you be willing to share your character sheet here so we can take a closer look?
To do so, click on your character’s portrait and pop out the sheet settings sidebar. Scroll down and update the share settings to let anyone with the link view your sheet, and then copy/paste the link here for us to look at. 
Here you go:
https://app.demiplane.com/nexus/pathfinder2e/character-sheet/ff8bde40-f686-4823-aece-4462aeead491
Maybe it’s because the Witch focus spells don’t seem to have any magic tradition associated with them, it’s not correctly including the proficiency bonus like it does for regular spells? Compare to the DC calculated for Fear:
+10 Base Value (Saving Throw)
+4 Intelligence Modifier
+5 Occult Proficiency Bonus (Trained)
Thanks for sharing! We’ll do some digging on our end and see if we can figure out what’s happening here and whether or not it should be doing something different.
I believe we have a fix in place for this, which you should see when our next update rolls out (exact date/time for that TBD). Please let us know if the issue is not resolved at that time.