Hi @dinartal
Many thanks for your reply !
Could you let us know which LPC546xx SDK are you using and which version? is the SDK_2.7.0_LPCXpresso54618?
Could you share your project with its config tools .mex file , or give us details on how to replicate the issue that you are reporting?
Below some images of the testing that I have done, using SDK_2.7.0_LPCXpresso54618 and MCUXpresso IDE v11.2.1 [Build 4149] [2020-10-07]

My peripheral settings for USBFS , yet I have not replicated your error.

My peripheral settings for USBHS, yet I have not replicated your error.

I am sorry for any inconvenience this may cause, as some errors that can be presented with specific software versions, SDKs and settings.
Many thanks
Diego