أحسن الله إليكم In manhaj as salikeen, it was mentioned that if someone had zakah on a certain type of wealth and then it changed to another type then the zakah remains. So if a man has 50kd zakah on gold and then he changed it to silver then the zakah is still 50kd? Is this correct?

Ustadh AbdulAziz al-Haqqan
Correct, once the zakah has fallen due it stays owed and exchanging the property does not drop it.