Cygnus OB2, within the Cygnus X complex, is one of the most active star-forming regions of our Galaxy, hosting hundreds of O and B-type stars across different evolutionary stages. Despite extensive studies of its massive stars, Cygnus OB2 exhibits a notable absence of fast rotating stars (v sin i > 200 ), which challenges existing models of massive star evolution. This study aims to investigate whether some stars classified as B0 in Cygnus OB2 are in fact rapidly rotating late-O stars, which could restore the expected tail of fast rotators in this region. We generated synthetic spectra using FASTWIND, and broadened and degraded them with the SpecBlur tool to evaluate the effects of rotation and noise on spectral classification. Using spectral reclassification methods and calculating projected rotational velocities with iacob-broad, we found approximately 30 % of the B0 population were actually late-O stars. Our work reveals a shortage of fast rotators in Cygnus OB2, even after reclassification, suggesting possible explanations including the young age of the region, alignment of stellar axes, and the potential ejection of fast-rotating stars as runaways.