Importing images depends much on the number of products imported and the performance of your server, and the process will take some time. Normally, if your import runs in the background, you must wait for it to finish; a message will indicate this.
You can enable the option (https://i.ibb.co/LnzXD18/image.png) to import to the Failed images section, then go there to manually import images.
We can discuss such problems on our support forum, we are glad to assist.