Apparently some countries use a fixed solfeggio method while others don’t. Meaning that in any diatonic scale the tonic would always be ‘do’ or if fixed ‘do’ wo

Apparently some countries use a fixed solfeggio method while others don’t. Meaning that in any diatonic scale the tonic would always be ‘do’ or if fixed ‘do’ would always be a ‘c’. This caused me some confusion how one could use solfeggio methods to acquire perfect pitch.