Hi Tarig,
If you want to use multiple parameters you have to add them to the deeplink microflow as string parameters. In your example you are using a Registration object, which can never be passed from a deeplink source.
First add the correct parameters, then check your deeplink configuration (run model reflection first). After selecting your updated microflow it should predict how your deeplink has to be formatted.
Also, check your DeepLink.RequestHandlerName. If you use "link/sharepointaccess/" your RequestHandlerName should match this.
Good luck!
EDIT: It seems you CAN use an object by providing the object id in your configuration, as Pim suggests.
You can use Registration as a parameter in your microflow chosen in the config but you should supply a unique identifier so the module can retrieve it for you.
See documentation:
Object Type
The fully qualified type of the object which need to be passed to the microflow. If empty, no arguments will be passed to the microflow. For example: MyFirstModule.Product.
Object Attribute
The attribute that will be used by the deeplink to uniquely identify the object that needs to be passed. In case of this value being configured empty, GUIDs will be used. If for example object type is set to 'User', and object attribute to 'Name', you can use links such as http://yourhost/link/showuser/MxAdmin