F5 ASM update failures

we get the below message when we try to update the Attack signatures via the F5 update API. f5 runs v13 we also see the issue on f5 v12s..anybody seen this ? var/tmp doesnt seem to have too many files ( no space issues i mean )

 

ASM Signature Update Failed for the device x.x.x.x. Reason -- Failed loading /ts/var/tmp/sigfile.tmp.6075/botsigs/200099690/13.1.0.xml (a HASH reference 05/21/2018 18:53:49 -