QUESTION ultimatepos 6.1 Error

I have installed ultimatepos 6.1, No error given on my website page, when i try register, it didn't redirect to login, just redirect to register page, and i try to login, i can't login,
But i when checked my log folder found below error
" production.EMERGENCY: File:/mydirectory/vendor/spatie/laravel-permission/src/Exceptions/PermissionDoesNotExist.phpLine:11Message:There is no permission named `sell.view` for guard `web` "
Please kindly give solution tips. Thanks