I have a frustrating problem I can't figure out.

I have a workcursor on a form created with
CREATE CURSOR WORKSPEC FROM ARRAY aFFLDS

When I am in a grid if I modify a field and tab out the command

replace workspec.artno with 'blah'

is executed.

If I move up and back to the same field and type a new value
the command

replace workspec.artno with 'blah2'

is executed.

At this point I get the error "record locked by another user"

The cursor is open excl
buffering is set to 5

In the command window I type
UNLOCK
REPLACE... &&same error

UNLOCK ALL
REPLACE... &&same error

TABLEUPDATE
REPLACE... &&same error

TABLEUPDATE(.t.)
REPLACE... &&same error

TABLEREVERT()
REPLACE... &&same error

TABLEREVERT(.t.)
REPLACE... &&same error

Two questions. Why does it do this?
Why can't I unlock it??
I need the buffering to detect changes in the lines.

Other grids built the same way do not have this behavior.

Any ideas?