Check if the license for the Quartus Standard edition you have purchased does include support for the Cyclone V SX devices. If not, then you may have to purchase licenses for these devices or change the device to one thats supported by your installed licenses.
Also check if the license setup is pointing to the right license file, if its a node-locked or floating license.
Can you perform a Flexlm license diagnostics and post the output here so that the Intel reps can check out if you have the correct licenses..
Licenses are for Quartus itself, not devices. If you have a license for standard edition, you can design for any device supported by standard edition. What is your license setup?
I have never seen nor heard of a device-specific license. There is no mention of this anywhere in the FAQ: https://www.intel.com/content/www/us/en/programmable/support/support-resources/download/licensing/q-and-a.html.