Monitor not working.Pool shows down.

Although your question is quite hard to read (didn't you notice that??), it's generally not recommended to set a timeout that is lower than the interval (actually I'm quite surprised that this is even possible). Try setting a timeout which is larger (f5 recommendation: 3 * interval + 1 seconds).

See https://support.f5.com/kb/en-us/solutions/public/12000/500/sol12531.html?sr=50894335 for further hints (this one also states "Configuring an appropriate interval/timeout ratio is important for simple monitors. In most cases, the interval/timeout should have a timeout value of three times the interval, plus one. For example, the default ratio is 5/16. Verify that the ratio is properly defined.")