Roth 401(K) loss

Received a 1099 R with distribution code "B" for 2024 because I rolled the total balance of a Roth 401k to Roth IRA.  
Plan administrator stated the dollars in the 1099 R were reported as a distribution because when I closed the Roth 401K, there had actually been a loss in the cost basis of my contributions.  I had effectively contributed more than I took out when I closed the Roth 401k to roll it. 

Found info on line and somewhat from IRS indicating when a Roth 401k is fully disbursed and closed, in that year only  I can report a loss as a Misc Deduction on Line 27 of Schedule A - which requires itemizing deductions.  (The amount of the rolled Roth 401k then becomes the cost basis in the Roth IRA.)
I cannot find how to enter this value from this 1099 R as a Misc Deduction.