Error message while running Strahler order for river delineation

I wanted to make river network using Strahler order in SAGA with filled DEM as the input, but there is an error message keep appearing:

QGIS version: 3.14.0-Pi
QGIS code revision: 9f7028fd23
Qt version: 5.11.2
GDAL version: 3.0.4
GEOS version: 3.8.1-CAPI-1.13.3
PROJ version: Rel. 6.3.2, May 1st, 2020
Processing algorithm…
Algorithm 'Strahler order' starting…
Input parameters:
{ 'DEM' : 'C:/Users/PERSONAL/Desktop/QGIS_results_HDP/fill_34.sdat', 'STRAHLER' : 'C:/Users/PERSONAL/Desktop/QGIS_results_HDP/river_34.sdat' }

io_gdal 0 -TRANSFORM 1 -RESAMPLING 3 -GRIDS "C:/Users/PERSONAL/AppData/Local/Temp/processing_KZPmeS/bbc1c29883054780acfc3d030361a759/fill34.sgrd" -FILES "C:/Users/PERSONAL/Desktop/QGIS_results_HDP/fill_34.sdat"
ta_channels "Strahler Order" -DEM "C:/Users/PERSONAL/AppData/Local/Temp/processing_KZPmeS/bbc1c29883054780acfc3d030361a759/fill34.sgrd" -STRAHLER "C:/Users/PERSONAL/Desktop/QGIS_results_HDP/river_34.sdat"

C:UsersPERSONALDocuments>set SAGA=C:/PROGRA~1/QGIS3~1.14/appssaga-ltr
C:UsersPERSONALDocuments>set SAGA_MLB=C:/PROGRA~1/QGIS3~1.14/appssaga-ltrmodules    
C:UsersPERSONALDocuments>PATH=C:PROGRA~1QGIS3~1.14appsqgisbin;C:PROGRA~1QGIS3~1.14appsPython37;C:PROGRA~1QGIS3~1.14appsPython37Scripts;C:PROGRA~1QGIS3~1.14appsqt5bin;C:PROGRA~1QGIS3~1.14bin;C:Windowssystem32;C:Windows;C:Windowssystem32WBem;C:PROGRA~1QGIS3~1.14appsPython37libsite-packagespywin32_system32;C:PROGRA~1QGIS3~1.14appsPython37libsite-packagesnumpy.libs;C:/PROGRA~1/QGIS3~1.14/appssaga-ltr;C:/PROGRA~1/QGIS3~1.14/appssaga-ltrmodules    
C:UsersPERSONALDocuments>call saga_cmd io_gdal 0 -TRANSFORM 1 -RESAMPLING 3 -GRIDS "C:/Users/PERSONAL/AppData/Local/Temp/processing_KZPmeS/bbc1c29883054780acfc3d030361a759/fill34.sgrd" -FILES "C:/Users/PERSONAL/Desktop/QGIS_results_HDP/fill_34.sdat"
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SAGA Version: 2.3.2 (64 bit)    
____________________________
library path: C:PROGRA~1QGIS3~1.14appssaga-ltrmodules
library name: io_gdal
library : GDAL/OGR
tool : Import Raster
author : O.Conrad (c) 2007 (A.Ringeler)
processors : 8 [8]
____________________________
    
Parameters    

Grids: No objects
Files: "C:/Users/PERSONAL/Desktop/QGIS_results_HDP/fill_34.sdat"
Select from Multiple Bands:
Alphanumeric Sorting: yes
Transformation: yes
Resampling: B-Spline Interpolation

loading: C:/Users/PERSONAL/Desktop/QGIS_results_HDP/fill_34.sdat

Driver: SAGA    
Bands: 1    
Rows: 19998    
Columns: 96657    
loading: fill_34    

C:UsersPERSONALDocuments>call saga_cmd ta_channels "Strahler Order" -DEM "C:/Users/PERSONAL/AppData/Local/Temp/processing_KZPmeS/bbc1c29883054780acfc3d030361a759/fill34.sgrd" -STRAHLER "C:/Users/PERSONAL/Desktop/QGIS_results_HDP/river_34.sdat"

C:UsersPERSONALDocuments>exit
Execution completed in 691.15 seconds
Results:
{'STRAHLER': 'C:/Users/PERSONAL/Desktop/QGIS_results_HDP/river_34.sdat'}

Loading resulting layers
**The following layers were not correctly generated.
• C:/Users/PERSONAL/Desktop/QGIS_results_HDP/river_34.sdat
You can check the 'Log Messages Panel' in QGIS main window to find more information about the execution of the algorithm.**

I have tried to change the target directory to the C:/ or D:/ to prevent the long directory name, if that is the problem, but the message keep appearing and I still cannot run the Strahler.

PS. I am using QGIS 3.14 and 3.16.