EFI Partition System shrank to a length of 0 bytes

Question

I used Partition Wizard on Windows to move the Windows Recovery Partition left to the unallocated place next to it, in order to do the same thing later to my Ubuntu partition, to give it more space. But when I rebooted on my Live USB Ubuntu, gparted complained

Can't have the end before the start! (start sector=1333248 length=0)

and consequently printed the disk in question (/dev/sda) as a unallocated space of ~1To.

Investating this with fdisk -lu, I found that my ESP had shrunk to a 0B partition, immediatly followed by an unallocated space which I think match the size of my former ESP:

Device          Start        End   Sectors   Size Type
/dev/sda1        2048    1333247   1331200   650M Windows recovery environment
/dev/sda2     1333248    1333248         0     0B EFI System
/dev/sda3     1865728    2127871    262144   128M Microsoft reserved
/dev/sda4     2127872  814739402 812611531 387.5G Microsoft basic data
/dev/sda5   814741504  816672767   1931264   943M Windows recovery environment
/dev/sda6  1431072768 1953523939 522451172 249.1G Linux filesystem

Do I have to create a fake >0B EFI System, to be able to use gparted, and then use boot-repair (which needs to have a new Bios-boot partition of > 1Mo to be created)? Do I have to use the Microsoft Recovery Partition?