Add record button to append the row into table and refresh the form for a new record entry MS ACCESS

will be helpful for those in need Too new to this site to leave this one as a comment, but part of your SQL string caught my attention "...,txtClassCode. numGrade,...". There's a period and a space in both your field string and value string.
As Remou suggested, "...try a debug.print strSQL and paste the result into the query design window to check for problems." You might also find it beneficial to just take the SELECT portion of your statement and get it working, then try the INSERT portion.

With these it helps Forms are visual representation of tables. With single forms, each record is displayed on each navigable page. Plus, single forms can have subforms. With continuous forms (multiple item forms) or datasheets, multiple records are displayed on a scrollable page.
You don't need to create a new form for each record but use same form that is filtered to a specific record using the DoCmd.OpenForm method's where argument. In your example, behind the button that opens other form, filter the opening form filtered to that particular trust:

DoCmd.OpenForm "OpeningFormName",  acNormal,  , "TrustID=" & Forms!MainFormName!TrustID"

Action: OpenForm  (search drop down)
Form Name: OpeningFormName (search drop down)
Filter: [leave blank]
Where Condition =: TrustID=Forms!MainFormName!TrustID
Data Mode: [leave blank]
Window Mode: [leave default of Normal]

will help you Figured it out! I just removed 100% of the code related to FormB and started from scratch.
On FormA, I added a simple...

Private Sub open_FormB_button_Click()
    DoCmd.OpenForm "FormB"
End Sub

Private Sub Form_Load()
    DoCmd.GoToRecord , , acNewRec
    Me.RequestID = Forms!API_BurndownPrimary_F!RequestID
End Sub

wish helps you
ActiveRecord::StatementInvalid (PG::UndefinedTable: ERROR: missing FROM-clause entry for table "computed_activity") LINE 1: ...tivities"."activity_id" = "activities"."id" WHERE "computed_...

Activity.joins(:computed_activity).where.not(computed_activity: {id: nil})

Activity.joins(:computed_activity).where.not(computed_activities: {id: nil})

With these it helps You are not missing anything.
The save logic (server-side) should: