How do I type Ñ on iMac keyboard, the hold and press method does not work anymore ?

I used to be able to hold the “n” on my imac keyboard and a pop up would appear where I could choose the “ñ”. For some reason this changed and this does not happen anymore. Now, if I click “n” it continues to type “n” (nnnnnn..) any ideas how i can switch it back to show “ñ” when I hold the key “n” ? Thanks

[Re-Titled by Moderator]