I work for a billing co we are billing an EM code and procedure code. We are getting paid for the procedure code but getting denied for the EM code ex. 99291 with 25 modifier and 31500. We are also having issues with inpatient billing 33960 on one claim then billing 33961 on subsequent claims. I tried appealing the denial referencing the billing of initial service. Can anyone shed some light on these issues.