PDFs not displaying mark ups or opening

My uploaded PDF's which have been marked up in WPS Office, are not displaying my mark ups when opened on Capacities Android app. They fail to open or download on the capacities via windows. This includes blank documents which solely have my handwritten notes on them.

See screenshot attached which shows thumbnails of the PDFs with all the mark ups displayed. When I try to open these on the android app the mark ups are absent. When i try to access on capacities via windows, the PDFs fail to open or download

This is of critical importance to me as i need the mark ups and notes for exams in three weeks. Please help!