Removed old filter, no issue. New filter would click, but not lock in. Tried several times, even repositioned the sliding lock to no avail. Tried the old filter, IT will not lock now either. Checked for o'rings or other debris, nothing visual.So I switched locks, no help. Put everything back on original filters, now the original still clicks but the new one won't even do that. Turned water valve way down and bled pressure, no help. Turned water completely off, no help. Am I looking at a new base?