IFTTT can't control Smartthings devices

I have created virtual switches to integrate some WiFi outlets with Smartthings using IFTTT. I created IFTTT widgets so when I turn on the virtual switch, the outlet turns on and when I turn off the virtual switch the outlet turns off Both of these work fine. What doesn’t work is I also created widgets for when the outlet is turned on/off, the virtual switch should be turned on/off. Neither of these work. I have tried this with two different brands integrated with the smart life app. It seems IFTTT is unable to change the virtual switches but can see when the virtual switches change and respond accordingly. Any idea why it is not working? Thanks!