I faced this too, and fixed it by:
1- removing all certificates of my account from keychain,
2- removing all provisioning profiles from xcode and then
3- downloading provisioning profiles again via xcode and also
4- adding certificates again to the keychain.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…