Sim not valid

After restoring my iPhone 6 i get the message:

"The SIM card that you currently have installed in this iPhone is from a carrier that is not supported under the activation policy that is currently assigned by the activation server. This is not a hardware issue with the iPhone. Please insert another SIM card from a supported carrier or request that this iPhone be unlocked by your carrier. Please contact Apple for more information."

Although the sim card is from the same carrier before the restoration.

Any help?