Hi.
Do you use Templates or Templater to create this notes or to introduce the metadata fields list?
If yes, then replace all “this” by (for Templates) [[{{title}}]]:
- Do Date:: `=[[{{title}}]].last-done + [[{{title}}]].postpone + [[{{title}}]].frequency`
If you don’t want to change anything (except the bedsheets, of course), make the calculation directly in your query:
last-done + postpone + frequency AS do-date