As JoeJ said, perhaps is this:
RAFT: what you call "SUPPORT", the 2/3 layers at the bottom whit grid pattern
SUPPORT (bridging): I think the problem you said, which are the odds. To avoid this, deactivate "
Generate Support" checkbox on "
FFF Settings" floating window.
I show you the image of a piece I've printed to illustrate the situation:
regards.
.