Components are usually used with a root view and in this case, the component handles the prefixing of IDs of views, elements, or controls, with the component ID.
This works similar to the prefixing of control IDs in XML views, see Support for Unique IDs. However, if you implement your own createContent function, you need to handle this yourself. The following two options exist:
Set the sap.ui5/autoPrefixId attribute in the manifest.json file to true. This is the easiest option.
Use the createId function of the UI component to prefix the respective ID of a view, element, or control yourself.
Use the byId function of the UI component to retrieve the views, controls, and elements that have been created in a UI component.