Assessment fee to get my phone back

I'm 18 months into my contract of my Sumsang A51, it just switches ON but does not go pass the stage. I took my phone for repairs and was told that it is out off warranty and that I should pay an amount of R245 to get my phone back as I am rejecting the quote ''It's an assessment fee they call it'' I will not be paying the R245 and will also stop all payments to telkom should I not receive my phone in 7 working days