have same problem now, after flushing full tank of badly smelling fluid at once with small pauses both windshield and headlight washers.
replaced headlights washer pump 8 months ago with no problems.
few weeks ago added waterlevel sensor and noticed leakege at headlightwasher pump hose, but not sure it was leak, maybe dropped from sensor hole... but its leaking now left front corner under car.
How you conected hoses after pump replacemant? with some lubricant or just brute force? cleaned both sides before ?