Hi,
Do you have Dynamics 365 F&O licenses in your subscription? This can be either customer licenses or a partner sandbox for Dynamics 365 F&O. Is this a complete new LCS environment or was it created e.g. last year or earlier?
Note that LCS has been deprecated for new projects. If you have a new LCS environment, you might need to go to Power Platform Admin Center (PPAC). From there, the new option is to deploy Unified Development Environments. It then does not support cloud hosted environments in your Azure tenant.
There is an option to ask for an exception by opening a support ticket, but I recommend to go with PPAC.