That's not necessarily a problem, it's usually a feature. Hibiscus, or something like it, is a tobacco add and the note is distinctively "soapy." Perhaps it is used because, like perique, it is acidic, which is used to round out alkaline VAs, or maybe some just like the flavor. Blenders - please chime in?
If it is hibiscus, you may be noticing it more as the tin dries. As I recall, some Gawith flakes were a common source at one time and perhaps still are. The soapy notes go away with aging, I assume because I haven't detected it in years.
I haven't searched "soapy" here or other pipe tobacco platforms, but you will certainly find some hits.