Nimbostratus
NimbostratusI think your Receive and Receive Disable strings are too similar. Both are probably being matched, resulting in an UP status.
notes that the strings are not case-sensitive when compared.
LTM Monitors Reference indicates that the member is marked UP when both Receive and Receive Disabled strings are matched.
Given this both of your strings contain 'active' and will be matched. Try changing the strings to something clearly distinguishable.
If that doesn't work you may need to enable monitor logging or capture traffic to be sure you're receiving the expected result from the server. I have run into issues where the server application performed caching that had to be cleared.