Why won't swift allow nested if statements along with others?

So for the past hour or so, I've been trying to nest three if statements in swift but nothing is working. I'm literally pulling my hair out for something that seems so simple and yet I have no idea what I am doing wrong. Any help is appreciated.

var population = 125442
var message: String
var hasAPostOffice: Bool = true

if population < 10000 {
    message = "\(population) is a pretty small town"
}else if population >= 10000 && population < 50000 {
        message = "\(population) is a medium sized town"
}else{
        message = "\(population) is a very large town!"
}else = {
    population >= 200000 && population < 120000 {
        message = "\(population) is a super huge town"
}
}
print(message)

if !hasAPostOffice {
    print("Where could I buy stamps?")
}