lumia starting new threads for messages

[David Buckley2]

My Nokia lumia has started to create new threads in my phone for exisitng sms message threads then said that contact cannot be found i have nokia luma 550 phone uk edition any ideas. I have an update waiting bit scared as lost messages..

 

[Guytronic]

Cloned IMEI or ESN perhaps?

 

[David Buckley2]

Nope its a sim i have had for ages on the gifgaff network