Hm. This sounds like the partiontable was not rewritten.
Just to make sure: with “after saving” you mean you have written back the changes with the ‘w’ command?
yes of course… 
I have the same problem. Dd in linux helped me with two of the three SD cards. Bud the third sd card always reset after clean… Same problem as yours.
dd if=/dev/zero of=/dev/X #replace X with the target drive letter.
Thank you this did the trick. Disk manager always had one 32mb partition not visible making 2 sd card unusable.
Strane… It does not work that way over here. Everything and every command is succesful, but at the end the three partions are still thetre and the sd card is not usable.
Doesn’t work on an sd card with has previously hassio on it.