Updating bug


I hope someone can help me :wink:

I have a little bug with core update on my Wordpress MU.
Since few weeks ago i had a "stopping" theme update because a server problem.

Now, i can't update my themes beacause the checkbox don't appear. ??
Do you have a suggestion ?
Is it possible to "reset" the update screen maybe ?
(Please see my screenshot)

Thank you guys !