Galaxy S3 Mini: "backing off 0" message on the screen

[dragos2222]

My Samsung S3 mini started to display the following message, "backing off 0", without a specific reason. This is like a post it that perhaps with 0 when I try to dial numbers, and it won't let me to access the 0 key. When I restart the device, the message dissappers for a while.
Is this a virus or just a settings problem?
thank you