Premiere Pro CC 2019 can't import .mp4 file

I start to edit the videos...but some videos (MP4 Files) are not working in premier pro.when i drag the video in the panel (on the Left side) it shows. But when i drag the video into the timeline only the audio work but the video is not working (It shows Blank Screen). I tried (https://community.adobe.com/t5/premiere-pro/premiere-pro-cc-2019-can-t-import-mp4-file/td-p/10365901?page=1) these two steps but the result is zero.Please help me to fix this problem....