Service Desk SLA (product workbench)

Hello,

We are having trouble setting the SLA for solman service desk.

We have setup the Availability and Reaction Schema with transaction CRMD_SERV_SLA.

We then setup he Categories and Hierarchies with transaction comm._hierarchy

Now when we come to setup the Product workbench with transaction Commpr01 we are getting the error:

An internal number range interval cannot be determined for category SLA

we tried to correct this by runing the transaction COMC_MATERIALID_ALL

This should allow us to set up the number range intervals for the product type Material.

But we get the error

No number range elements (base categories) can be determined

Any idea what is the problem? How can this be corrected?

Regards,

Avrohom