AS/400 can lock only one record per open data path.
This means that, when a record lock is requested on a file by a WinDev program, the previous record locked applied to the same file, by the same program, is released. Except when using independent contexts, or inside a transaction.
Locking the whole file is possible.
When using idenpemdent HyperFile contexts, set connection property DUPPATH, to have one open data path per file and per context, and allow each context to have its record lock.