All DPF-API APIs other than GET are asynchronous.
Although asynchronous APIs return a response as soon as they receive a request, the actual process for the request is performed asynchronously.

When multiple updates are executed for a single record before the actual process for a request is performed, the last update content is reflected because there is no lock function.
With regard to jobs to be input in actual processing, it is not guaranteed that the jobs are processed in order of the input of update contents. To process them in order of the input, confirm the end of processing every time you input a job.