Invalid expression: Expression incomplete error

I’m trying to write a simple case statement in custom dimension but I’m getting

Invalid expression: Expression incomplete error Can some one please help me.

case when ${d_cus_lu.ltd_sls_amt}<5000 then “Less than 5000”
when ${d_cus_lu.ltd_sls_amt}>=5000 AND <10000 then “Between 5000 and 1000”
else “Greater than 10000”
end