Why is CrudRepository ignoring a @Column?

I have an object model that looks like this:

public class Agreement {
    @Id @Column(name = "AGREEMENT_ID") private String agreementId;

    @Column(name = "RATE") private String rate;
    @Column(name = "NOTE") private String note;
    ... // A number of other fields
}

Each field has getters and setters, as generated by IntelliJ, verified these are all correct. On my GUI, the user has the option to make changes to an agreement, then hit "Save". Now my server needs to make the update on the back end. I'm using Spring Repositories and so I have:

@Repository
public interface AgreementRepository extends CrudRepository<Agreement, String> {}

When the user makes the submission I invoke agreementRepository.save(agreement). However, one of my fields, rate is not being updated on the back end.

I have stepped through the code and verified that the rate property is set correctly in the agreement object being passed to save(). Further, I have printed the SQL and verified that it is in fact at this level that the issue seems to be occurring, noting the save() method is calling a SELECT followed by UPDATE as expected since I'm modifying the same entry over and over in testing, but I can see clearly in the UPDATE part of the query that the rate field is not being set.

Odder still, ALL other fields are being set properly, regardless of whether I am also setting RATE or not. All other changes are propagating through just fine. There is nothing unusual about this RATE field. I thought maybe there was a bad trigger or something that a developer before me had put in, but I can see that the UPDATE SQL generated by Spring is clearly not setting it, and have verified no such triggers exist.

What is the reason that CrudRepository.save() would ignore one of my fields? It is not marked @Transient and is not unusual in any way. If it is not CrudRepository where else should I look to see why this field is not being set correctly?