Chipping lanes

My puppy was microchipped soon after we rescued her. She is now seven months old and I’ve noticed it has migrated from her down to her below her shoulder.
Might this present a medical problem?

And also, if she is ever lost and scanned, will a scanner pick her chip up as it has moved from her neck? Should I have her chipped again?

Charlotte White, by email

Chip fail

Can you do anything to highlight the problems with failed chips? I was assured by Virbac that my chip would continue to work. We are currently in Switzerland and his chip has failed. I now have to leave him behind and come back for him when his Swiss passport is valid. I know that I am not the only one. They should be replacing all of these chips not just waiting for them to fail. This is causing me a massive amount of emotional stress! 

Many thanks,

Karen Walker, by email