Split switched receptacles all stay hot regardless of switch position
Two things come to mind:

Make sure the switches are actually working by disconnecting the load wire and testing for voltage passing through or resistance between the terminals.
Verify that the red wire believed to be the switched hot at the outlet actually goes to the switch. Could do this by identifying which outlet is the first in the series, disconnect the red wire from that outlet, then confirm that toggling the switch causes the voltage on the wire to toggle.

After checking these you'll know whether the switch works properly and whether it controls the wire going to the first outlet in the series. This will help you isolate the problem to the switch itself (contacts welded closed), the space between the switch and first outlet (switch doesn't actually control those outlets, for example), or something in or beyond the series of outlets (the switched-hot is possibly backfed from same or another circuit somewhere).