Hi there @sandman2053,
Thanks for asking about the Spotify Web Player!
There should be no limitations to play on-demand songs in the Web Player when using Spotify Premium. Since it works fine on your Desktop device at home, the same should be on the computer at work.
Please make sure you don't have a second account. After that, log in on the computer at work with your Premium login data by entering it manually.
Additionally, you could try clearing the cache from your browser and try again. If the situation stays the same, please send us a screenshot of how the Web Player appears on the work computer and of the error message when you try to play songs on-demand.
Let us know how it goes!
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