Plateau after shifting to wegovy

Started Oz in April, lost around 20lb in 6 months and for insurance purposes was changed to wegovy

Have not lost a single lb since then and some weeks even gained

Is that normal? Aren’t they supposed to be the exact same medicine?

Context: started oz 0.25x4 then 0.5x4 then 1x4 and then shifted to wegovy at 1 weekly