How to add allow new added user to access existing folder with SFTP?

My goal is to add a new user and give him SFTP access on an already existing folder (web) : I need the user bigsquash to have access to folder /home/bigsquash.com

The existing folder is:

ls -la /home/bigsquash.com

drwxr-xr-x 27 www-data  www-data  4096 Oct  5 23:48 bigsquash.com

1. I add a new user

   adduser bigsquash

2. I add that user to the www-data group:

   usermod -a -G www-data bigsquash

3. j'ai changé son home

   usermod -d /home/bigsquash.com bigsquash

I can now access with SFTP to that folder /home/bigsquash.combut I have no rights to upload/delete files

What