Problems With Universal Clipboard

One thing I love about using a Mac and a iPhone is universal clipboard. That is, I love it when it works, which is not much of the time. I can copy a block of text on one device and, usually, it won’t be present on the clipboard of the other device. Sometimes, it will work after trying a few times. I have read that it can help if you sign out of and back into iCloud on your Mac and iPhone. I have done that but it only fixes the problem for a day or so. Sometimes, rebooting the mac and the iPhone fixes the problem but that doesn’t always work and, even when it does, it is only temporary. Do others experience this issue and, if so, have you found anything you can do to make it work more consistently? I am using a 2015 Macbook Pro, running High Sierra, and a iPhone 6S, running IOS 11. I had this problem both before and after the update to the new operating systems.