unresponding cp between two remote cifs share, both on the same distant machine

I have 2 cifs remote share in /etc/fstab on xubuntu machine

//192.168.1.2/THOMAS /media/THOMAS cifs credentials=/root/.smbcredentials,_netdev,iocharset=utf8,vers=2.0,nofail,cache=none,uid=1000,forceuid,gid=100,forcegid 0 0//192.168.1.2/JACQUES /media/JACQUES cifs credentials=/root/.smbcredentials,_netdev,iocharset=utf8,vers=2.0,cache=none,nofail,uid=1000,forceuid,gid=100,forcegid 0 0

the mount cmd give me

//192.168.1.2/JACQUES on /media/JACQUES type cifs (rw,relatime,vers=2.0,cache=none,username=toto,domain=WORKGROUP,uid=1000,forceuid,gid=100,forcegid,addr=192.168.1.2,file_mode=0755,dir_mode=0755,iocharset=utf8,soft,nounix,serverino,mapposix,rsize=65536,wsize=65536,bsize=1048576,echo_interval=60,actimeo=1,closetimeo=1,_netdev)//192.168.1.2/THOMAS on /media/THOMAS type cifs (rw,relatime,vers=2.0,cache=none,username=toto,domain=WORKGROUP,uid=1000,forceuid,gid=100,forcegid,addr=192.168.1.2,file_mode=0755,dir_mode=0755,iocharset=utf8,soft,nounix,serverino,mapposix,rsize=65536,wsize=65536,bsize=1048576,echo_interval=60,actimeo=1,closetimeo=1,_netdev)

on 192.168.1.2 (debian machine) the smb version is

sudo smbstatus --versionVersion 4.13.13-Debian

on local machine the smb version is

sudo smbstatus --versionVersion 4.18.6-Ubuntu

For example, when i copy a file from JACQUES to a local disk, i have no problem.

But when i try to copy a file from JACQUES to THOMAS, it hangs. nothing in top, nothing in iotop, i see the file is created in the destination folder but it stays to 0 byte. And when i try to cancel the copy, nothing happened.

I tried with ver=3.0, i tried with cache=strict and before some days i haven't the problem.

when i try to mv a file, smbstatus tells me :

sudo smbstatus -LLocked files:Pid          User(ID)   DenyMode   Access      R/W        Oplock           SharePath   Name   Time--------------------------------------------------------------------------------------------------21140        1000       DENY_NONE  0x120089    RDONLY     LEASE(RH)        21140        1000       DENY_NONE  0x120196    WRONLY     LEASE(RWH)

and nothing with iotop on the client.

reminder : the problem only happen if source and destination are two different share folder on the same machineand i have no problem doing exactly the same mv on Windows :-(

could somebody help me ? thank you.

PS: sorry for my poor english ;-)