I have a 20month gsd that will not toilet away from
Home.We where away for the weekend left on the
Fri mor but it wasn't until the Sunday she done anything
Anyone think of anything I can do have taken toilet
With me out with other dogs nothing seems to help

This is an instinct. Away from her home range she will be very reluctant to leave her scent. As long as she stays hydrated there should not be a big problem.

One thing you might try, and it may or may not work, is taking her into remote, hidden places to go. If there's bare dirt she can bury her scent with that's all the better.

Thank you will tryhat.just don't like the idea of her
Going 3 days can't be go for her.but will give it ago