While importing dashboard with Grafana api - gridPos changing to default value

Hello
I have dashboards generated with Graffonet that I need to import to Grafana. I’ using Ansible with grafana_dashboard module and tried import with uri as well. In all cases while I’m importing panels under Raw - gridPos changing to default value (w: 8).
I even took json from Grafana itself, updated gridPros and imported this file - still gridPros was reverted to default.
BUT, if I import panels without Row - all works as expecting. I can set gridPos and Grafana changed panel size.
Does someone know how to fix this issue? This is annoying, cause all other things works fine.