I just made up a language. It's called AJTI#IS$35.$

Here are some English nouns and their translations in my language: cat $=$ FUSI$429$; phone $=$ VZIO$222$; blanket $=$ GJIS$59202.$

Here are the plural forms of those same English nouns and their translations in my language: cats $=$ FUSI#$429$; phones $=$ VZIO#$222$; blankets $=$ GJIS#$5902.$

What is the morpheme for plurality in my language and how is it affixed?