Epson do make the same printer models available in different parts of the world - however to control market prices they may need to offer cartridges for the printer cheaper in poorer countries.

To stop customers buying the cartridges which are sold cheaper in different country and importing them and using them on their own printer, they make the chips / cartridge numbers different it is called regional zoning of chip (different parts of the world

An example would be un the Uk for epson WF-3720. we use T3471 cartridges. in Australia they use 702 carts - on all our products we advertise the chip numbers so it is always worth checking

There are around 8 regions in the world.

To get around this and use this product you would need to install a firmware update called chipless firmware if its available a from a company called inkchip which disables the chip monitoring