Mapbox API - Optimization v1 - Co-ordinates not recognising, can you help?

Hi everyone. I’m wondering if any of you have encountered this problem and might know how I could resolve it.

I’ve setup Mapbox via API (optimization v1).
I’m trying to pass a list of co-ordinates from a repeating group (Theyre stored in my jobs Datatype) into the mapbox api and get a waypoint response back, so I can order the repeating group by the waypoint order. Optimized route order basically.

I’ve so far managed to get the API to connect successfully however it seems it doesnt recognise my co-ordinates and is throwing out an error that there are less than 2 coordinates, and then this message in step-by-step debug

{“message”:“Not enough input coordinates given; minimum number of coordinates is 2.”,“code”:“InvalidInput”}

Iv attached some screenshots which may help.

Please please if you know what I’m doing wrong tell me what. I’ve been going round in circles. I’ve used bubble searh to see if there were any other posts regarding this but there aren’t, so as my last resort I’m asking you guys for help if you can.

Many thanks
Derek