Assistansts API pdf upload doesnT work anymore

Since this morning, my upload of a pdf-file to openai doesn#T work anmore.
Since this is my testing-file, I#ve uploaded it a dozen of times before in the last weeks. But now I get the error message:
‘error’: {‘message’: 'Invalid extension PDF. Supported formats:

my Code:

@app.route(‘/uploadMessageFile’, methods=[‘POST’])
def upload_message_file():

data = request.json
file_path = data.get(‘file_path’)
file_content = data.get(‘file_content’)

response = client.files.create(file=(file_path,base64.b64decode(file_content)), purpose=‘assistants’)
message_File_IDs.append(response.id)
print(“==========RESPONSE UPLOAD ========>”, response)
return jsonify({“response”: response.id})

It’s really strange, because it worked without problems before…
Any suggestions?