File not found even if it is existing

I have a CLP which declares a file:

             DCLF       FILE(QTEMP/TEMPFILE)

When I compile it, it will have an error:

CPD0852 30 File TEMPFILE in library QTEMP not found. So, I tried to create it:

CRTPF FILE(QTEMP/TEMPFILE) RCDLEN(150) SIZE(*NOMAX)

But it still cannot be found when I compile.

Note that I'm creating and compiling the file in the same session.

What I tried to do is to edit the authority and grant access to all:

EDTOBJAUT OBJ(QTEMP/TEMPFILE) OBJTYPE(*FILE)

So here is what it looks like:

                             Edit Object Authority                              
                                                                                
 Object . . . . . . . :   TEMPFILE        Owner  . . . . . . . :   PAXUS        
   Library  . . . . . :     QTEMP         Primary group  . . . :   *NONE        
 Object type  . . . . :   *FILE           ASP device . . . . . :   *SYSBAS      
                                                                                
 Type changes to current authorities, press Enter.                              
                                                                                
   Object secured by authorization list  . . . . . . . . . . . .   *NONE        
                                                                                
                          Object                                                
 User        Group       Authority                                              
 *PUBLIC                 *ALL                                                   
 *GROUP      PAXUS       *ALL                                                   
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                         Bottom 
 F3=Exit   F5=Refresh   F6=Add new users   F10=Grant with reference object      
 F11=Display detail object authorities     F12=Cancel   F17=Top   F18=Bottom    
 (C) COPYRIGHT IBM CORP. 1980, 2018.                                            

Please help me why I can't compile it due to missing file even if it is existing.

Because you have your compiles set to run in batch.

Since QTEMP to unique to a job, the file doesn't exist in the submitted job's QTEMP.

Quick and dirty solution is to run the compile interactively. I'd hope you aren't using PDM. But if you are, from "Work with Members", F18=Change defaults then change Compile in batch . . . . . . Y

The real solution is to use an actual change management system, or at least some build tooling.