node.js - dynamo db error Invalid ProjectionExpression: An expression attribute name used in the document path is not defined; attribute name: #P -

i trying , delete data dynamo db using 2 primary key column, in 1 reserved keyword timestamp.

when data using 1 of primary key working fine, when trying delete using 2 primary key field in projection expression giving me error :

validationexception: invalid projectionexpression: expression attribute name used in document path not defined; attribute name: #p

and params object

{ tablename: 'log', projectionexpression: 'username, #p', expressionattributenames: { '#p': 'timestamp' }, expressionattributevalues: null }

username , timestamp primary key columns.

this thing not working in table. in others table have same situation not throwing me error. in case getting error.

the deleteitem api not allow specify projectionexpression. can entire pre-deletion image of item selecting returnvalues = all_old.