Sentinel-2 L2A Processing Baseline number incorrect after running sen2cor

Hello all,

I processed Sentinel-2 L1C into L2A by running sen2cor 2.8.

The Nxxyy: the Processing Baseline number changes to ‘N9999’ for all the tiles I process whereas the original L1C Nxxyy is ‘N0207’. Anyone know what could have gone wrong?

Many thanks,