Strange Issue - Failover is not working Please Help

I have 2 ISPs and 2 LAN configured in Mikrotik
ISP 1 is is for LAN1 and ISP 2 is for LAN2
i have configured NETWATCH to monitor Both link if any ISP goes down the whole traffic for LAN 1 and LAN 2 starts to going through the Connected ISP.
for this i have configured 2 different static route for both ISP and dropping in firewall filter these static routes not to reach from other ISP in order to work NETWATCH properly

this Method was Working Great since 3 month but today my ISP1 went down, all traffic has been shifted to ISP2, while ISP1 got back, but my traffic did not go back on their specific ISPs. I checked NETWATCH , ISP1 Status was still DOWN. I made a ping from Mikrotik to that IP which was mention to monitor the traffic for ISP1 , it is coming request time out. and on traceroute from Mikrotik tools. trace route is successful through ISP1.

Pinging that IP from any LAN of mikrotik is also successful bot not from router itself.
what could be the issue please help ???

Post your ip>routes rules here