Thanks for reply! It seems you have deny assignment for this resource group, To elaborate, Similar to a role assignment, a deny assignment attaches a set of deny actions to a user, group, or service principal at a particular scope for the purpose of denying access.
Deny assignments block users from performing specific Azure resource actions even if a role assignment grants them access.
This article describes how to list deny assignments using the Azure portal.
Further Deny assignments are created and managed by Azure to protect resources. Azure Blueprints and Azure managed apps use deny assignments to protect system-managed resources. Azure Blueprints and Azure managed apps are the only way that deny assignments are used within Azure.
You can't directly create your own deny assignments. Azure Blueprints uses deny assignments to lock resources, but just for resources deployed as part of a blueprint.
For more information, see Understand resource locking in Azure Blueprints.
Let me know if further assistance is needed.