Help, I have a question about data provider filtering using relationship picker.

[neojigi]

using DB : internal DB

table A : Parts
table B : Maker

relationship : Parts (Many) ~~~ Maker (One)
relationship name : mmm

/parts

• New Form ::: Parts
  • Relationship picker ::: mmm
  • Data Provider ::: Parts
    • Table ::: Data Provider

I set the filter of the data provider as follows

column : _id
condition : equal
type : bind
content : {{ New Form.Fields.mmm }} <--- mmm is relationship name

After setting it up as above, when I select what I want from the relationship picker in the preview screen, the contents of the table shows nothing.

What did I do wrong?