Program Stage is not include in tracked entity instance query API

Dear DHIS Community,

I have found one bug in “http:localhost:8080/api/30/trackedEntityInstances/query.json”.This API from Tracker capture API it is sendg the parameter from UI side>but in back end you have not configured any program Stage as a parameter in API.please find the screen shots for your refernce.Also Suggest me how can move forward from this bug.I am using DHIS2.34.1 version

input:
http://localhost:8080/dhis/api/30/trackedEntityInstances/query.json?ou=pcoTcNRJVal&ouMode=SELECTED&&order=created:desc&program=mgQS5cw2rVi
&programStatus=ACTIVE&eventStatus=SCHEDULE
&eventStartDate=2020-07-27&eventEndDate=2020-11-04
&programStage=qX9NFx2ZCdT&assignedUser=&pageSize=50&page=1&totalPages=falsehttps://savemyanmar.duredemos.com/service/api/30/trackedEntityInstances/query.json?ou=pcoTcNRJVal&ouMode=SELECTED&&order=created:desc&program=mgQS5cw2rVi
&programStatus=ACTIVE&eventStatus=SCHEDULE
&eventStartDate=2020-07-27&eventEndDate=2020-11-04
&programStage=qX9NFx2ZCdT&assignedUser=&pageSize=50&page=1&totalPages=false

API source code: