An error occured while uploading files

Nextcloud version 15.0.5 :
Operating system and version Centos 7 64bit :
Apache or nginx version Apache/2.4.6 (Centos) :
PHP version php 7.2.11(cli):

Mail Version: 0.11.0
There are two types when uploading o attaching of files data

  1. Upload attachment
  2. Add attachment from files

using Upload attachment is error button of send is become grey or inactive cannot be click

Using Add attachment from files is nothing problem its working fine

This problem happened when i upgrade my NC into latest version

Is this a bug from Mail Apps?