wifi.sh second time connection fail

[larryle]

I am using piCore 8 and using a usb wifi adaptor on PI3.
I add
/usr/local/bin/wifi.sh -a in the /opt/bootlocal.sh so that, every time it boot up, will connect to my wifi automatically. that's ok. all working and I can ping google.com without issue.

But the problem is,  I did following test, turn off the wifi router,  then turn it on.
My program on the pi3 will trying call wifi.sh -a again to reconnect.  it can get a ip address everything seems fine, but cannot access internet anymore.

so, then I run the route command twice,
1: one after start up when internet is ok(can ping google.com), I can see one extra ip info (above red line)
 

2: then I manually run wifi.sh -a command again, I got same ip address but CANNOT ping google.com
then run route command, I got this,
 


so, did I do something wrong?  how could I fix it?

tks
Larry