Vassals not paying tax

I'm playing with tribal government and on my character's page under the vassals tab, it lists tribal vassals with no tax (as expected) and a handful of city and temple vassals that pay various amounts of tax fully (green, no penalties). However, in the title page where it lists your realms income and expenses, it doesn't list any city or temple income, nor am I receiving any. My tax rates for both temple and city are high, I'm within my vassal and demesne limits, so I have no clue why it's not giving me the income.

Solution 1:

Apparently having a holding of wrong type in your personal demesne for enough time nullifies your vassal income; the popup doesn't say so, but as soon as I gave away all non-tribal holdings I received tax again.