App force closes when I click the Mp4 download option

[dongentle2]

I have been trying to download videos in mp4 format in the latest update but it keeps crashing whenever I hit the download button.

Describe the bug
The app crashes whenever I try to download a video on Mp4 format. I can stream well but whenever I hit the Mp4 download option, it loads and then crashes.

** Steps To Reproduce**

Launch the app
input the search words ( in my case I wanted to download MGK rap devil)
click on your desired video from the search results.
click download mp4
starts converting and the error shows.

Expected behavior
When I carried out this operation, I expected it to convert and start the download but it kept crashing.

Screen recording
https://youtu.be/ug3jrHT3azM

Test Environment

Device: Infinix Hot 7 Pro
OS: Android 9.0
Software version: Music Downloader version 1.3.11
Logcat
Here is the full Inbuilt android logcat for the period
bugreport-H624EF-PPR1.180610.011-2019-07-02-11-10-31.zip

[cioccarellia]

Will check it out, thanks for the catch

[AGCMP3]

Same with me, download Mp3 is fine. But mp4 produce an error