Differences in granules spectral values

Hi there,
I have downloaded two Sentinel-2A adjacent granules from ESA and performed reflectance conversion and atmospheric correction (DOS)using the Semi-automatic Classification Plugin in QGIS.
The problem is that the spectral values of adjacent granules are different (see attached pictures).
Does somebody know why this problem occurs and how to solve it???
Any help shall be greatly appreciated.

Dear Gari,

This is not clear to me whether you observed those discrepancies with the original L1C tiles before the processing you performed.
If it is the case, please raise a ticket to eosupport@copernicus.esa.int and provide them with more information about the tiles you used.

Thanks and regards
Olivier

Dear Olivier,

Thank you for your response.
The discrepancy occurs only after atmospheric correction in QGIS. And now it seems to me that the problem may be due to the fact that the adjacent granules were processed separately, which cause this variation in wavelengths.

Regards
Garik

Dear Garik,

Thank you for the clarification, it sounds understood.

Regards
Olivier