2 isp and nat

Hello! I have new ISP and want to test it, so I configured routing instance and additional security zone. Everything seems fine so far, but I cant switch nat to second isp.

Security zone for second ISP

show security zones security-zone isp2 
host-inbound-traffic {
    system-services {
        ping;
        ssh;
        ike;
    }
}
interfaces {
    fe-0/0/4.0;
}

show security policies from-zone trust to-zone isp2 

Security policy for second ISP:

policy trust-to-isp2 {
    match {
        source-address any;
        destination-address any;
        application any;
    }
    then {
        permit;
    }
}

Source NAT rules:

pool default-ip {
    address {
        62.176.7.74/32;
    }
}
pool MX {
    address {
        62.176.7.61/32;
    }
}
pool cifra1 {
    address {
        79.134.86.54/32;
    }
}
rule-set nsw_srcnat {
    from zone trust;
    to zone untrust;
    rule MX {
        match {
            source-address 192.168.70.253/32;
            destination-address 0.0.0.0/0;
        }
        then {
            source-nat {
                pool {
                    MX;
                }
            }
        }                               
    }                                   
    rule isp1 {            
        match {                         
            source-address 0.0.0.0/0;   
            destination-address 0.0.0.0/0;
        }                               
        then {                          
            source-nat {                
                pool {                  
                    default-ip;         
                }                       
            }                           
        }                               
    }                                   
}   
inactive: rule-set isp2-nat {           
    from zone trust;                    
    to zone isp2;                       
    rule ALL-NAT {                      
        match {                         
            source-address 0.0.0.0/0;   
            destination-address 0.0.0.0/0;
        }                               
        then {                          
            source-nat {                
                pool {                  
                    cifra1;             
                }                       
            }                           
        }                               
    }                                   
}   

If I switch default rule for nat from ISP1 to ISP2 users wont have access to internet. Whats wrong?