There are two main reasons this could happen
1) you set it up in a way that you need to press an input to interact
2) the interactable layer does not contain your character
I see you are using the character controller integration with the inventory system. That means you can setup your inventory pickup the character way with the pickup ability or the inventory way with the inventory interactor.
The documentation for the integration has a section for the item pickup that explains the difference between the two:
The character controller is seamlessly integrated with the Ultimate Inventory System allowing you to use the Ultimate Inventory System inventory rather than the inventory included . . .
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In your case since you followed the "Getting Started with the Ultimate Inventory system" video I assume you have chosen to use pickups using the inventory way.
You can learn more about it here:
Item pickups are components used to “pickup” items using an Interactable (the Item Pickup) and an Interactor (the character). There are multiple types of pickups: . . .
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and here
The inventory system requires a lot of interactions to pickup items, open chests, open a menu, etc. An interaction system has been created in order . . .
opsive.com
Essentially you can choose whether you automatically interact (auto pickup) by toggling on the auto interact field on.
You could instead use an input to interact, this can be done on input down for example.
On the Interactable component you may also choose whether you auto interact or not. This will force the auto interact even if the auto interact is off on the inventory interactor.
The last important thing is the Layer. The interactable can only be interacted with if the interactor matches the layer:
Once you've setup your interactor and interactable correctly you should be able to interact with your pickup.
Make sure that your trigger collider (and physics collider if your pickup is not kinematic) are big/small enough such that you character can interact with it normally. Of course make sure that your colliders and centered with the visual part of your item.
Last side note, the Integration works mostly with Inventory Pickups instead of item pickups. For item pickups we use the "Item Object Visualizer" component to switch the 3D model you see on the pickup. For Inventory pickup you can use the "Inventory Item Visualizer" instead. It can be used to show the 3D model of the first item in the inventory of the pickup.
Learn more about this useful component here:
Item Object Visualizer The Item Object Visualizer is meant for the Item Object to take shape in the game world. This is done by swapping . . .
opsive.com
If you find anything that isn't clear in the documentation please let us know and we'll fix that asap
