This kind of situation can have two sources. The first can be managed by yourself and the second only by DQE, as it is included directly in the package.
The first part consists of checking whether the field is accessible by the profile of the user who reported the problem.
Another reason may also come from validation rules, but if the problem has not been reproduced on the classic Salesforce form, then you won't be able to do anything.
If this is the case, and a data item is modified but not saved, then you need to create a DQE support ticket: support_dqe@dqe-software.com.