Safety of Using Janess IUD Beyond 3 Years

[worried1919]

Hi, 
I've been using the Janess IUD for over two and a half years. 
At some point my period stopped, so most of this time, I haven't had my period. 

During my recent check-up, my doctor examined the device and mentioned everything is fine, advising I can continue using it for at least another year, even though the device's instructions suggest a maximum use of up to 3 years. 

Is it common or safe to use these IUDs beyond their recommended duration if my periods have been irregular or absent?

Is it safe enough?