Try this as it sounds like a simple matter of new cable stretch.
Tighten both ends of the cable back into the lever and caliper. Loosen the bolt holding the cable. Using your hand pull the slack out of the cable. Then tighten the fixing bolt agian. This should give you more options. And for crying out loud you've got WAY too much loose cable on that disc brake. Clip it down to where it can't get sucked into the caliper