I'm having the same problem after porting on a sim only contract.
Moved from 3 to ee. Received message saying porting complete, but it looks like I'm unable to receive verification sms messages or messages from companies regarding deliveries. I can however send and receive messages for people in my contact list.
I also noticed that the sim card number was still the one that ee provided and not my old number. Managed to fix that by putting the sim card in my partner iphone (my phone is a samsung). Unfortunately, it looks like I'm still having problems with receiving some sms messages.
I spoke to customer support and was told to contact the companies that I'm not receiving messages from, to find out the number they use so that I can check they aren't in my blocked numbers list. I know that they are definitely not in my blocked numbers list as I received an sms from them the day before I ported.
