Problems since IOS 15.6.1

Ever since this update both of my iPhones and many other members of my family have problems receiving texts or making outgoing phone calls. The calls would go right to voicemail and the receiver would have no indication of a missed call. As for text messages they would appear to go through but again the receiver would have no indication of a new text message. I’ve tried removing my Sim card rebooting numerous times resetting my carrier, to no avail. I have now reverted to using WhatsApp for calling and texting. Any suggestions?. Thank you in advance