Django acting weird on Windows server IIS deployment - django

Question

I have the following view which allows me to save the information of a multi step application.
def saveNewApplication(request, *args, **kwargs):
educationList = [ val for val in pickle.loads(bytes.fromhex(request.session['education'])).values() ]
basicInfoDict = pickle.loads(bytes.fromhex(request.session['basic_info']))
documentsDict = pickle.loads(bytes.fromhex(request.session['documents']))
applicant, created = ApplicantInfo.objects.update_or_create(
applicantId=request.session['applicantId'],
defaults={**basicInfoDict}
)
if created:
#saving the diplomas
for education in educationList:
Education.objects.create(applicant=applicant, **education)
with open(f"{documentsDict['cv_url']}/{request.session['file_name']}", 'rb') as f:
Documents.objects.create(
applicant=applicant,
cv =File(f, name=os.path.basename(f.name)),
langue_de_travail = documentsDict['langue_de_travail']
)
#remove the temporary folder
shutil.rmtree(f"{documentsDict['cv_url']}")
else:
educationFilter = Education.objects.filter(applicant=applicant.id)
for idx, edu in enumerate(educationFilter):
Education.objects.filter(pk=edu.pk).update(**educationList[idx])
#updating the documents
document = get_object_or_404(Documents, applicant=applicant.id)
if documentsDict['cv_url']:
with open(f"{documentsDict['cv_url']}/{request.session['file_name']}", 'rb') as f:
document.cv = File(f, name=os.path.basename(f.name))
document.save()
document.langue_de_travail = documentsDict['langue_de_travail']
document.save()
languagesDict = pickle.loads(bytes.fromhex(request.session['languages']))
Languages.objects.update_or_create(applicant=applicant, defaults={**languagesDict})
if 'experiences' in request.session and request.session['experiences']:
experiencesList = [ pickle.loads(bytes.fromhex(val)) for val in request.session['experiences'].values() ]
Experience.objects.filter(applicant=applicant.id).delete()
for experience in experiencesList:
Experience.objects.create(applicant=applicant, **experience)
return JsonResponse({'success': True})
In the development it works perfectly but if deployed I am getting a 404 raise by this line get_object_or_404(Documents, applicant=applicant.id) meaning the creating is false. and I can't figure why is that.
The weirdest thing is if I do comment the entire else block it also returns a 500 error but this time it I do click in the link of the console it show the right response not redirected {success:true}
down below is my javascript fonction for handling the view.
applyBtn.addEventListener("click", () => {
var finalUrl = "/api/applications/save-application/";
fetch(finalUrl)
.then(res => res.json())
.then(data => {
if (data.success) {
window.location.href = '/management/dashboard/';
} else {
alert("something went wrong, Please try later");
}
})
});
I am using postgresql as a database I deleted twice but nothing.
the url file is here.
path("api/applications/save-application/", views.saveNewApplication, name="save-new-application"),
path("api/applications/delete-applicant/<slug:applicantId>/", views.deleteApplicant , name="delete-applicant"),
path('api/edit-personal-info/', editPersonalInfo, name="edit-personal-info"),
Any help or explanation would be highly appreciated. Thanks in advance.