Instant Run instruments your app and may cause issues with how hansel performs bytecode enhancements. If you experience these issues, but want to continue using Instant Run, you should disable hansel for your debug build variant. Android recommends that you should disable other tools (such as Crashlytics, Proguard) as well if you choose to use Instant Run in debug mode. Check out our section on how to do disable hansel for specific build variants.
Alternatively, if you want to have hansel enabled even in debug mode, you can switch Instant Run off by going to Settings → Build, Execution, Deployment → Instant Run and uncheck Enable Instant Run.