Backup errors

BackWPup has ceased working. It has successfully backed up 5 times since 2018. I have cleared all the old backups from Dropbox, so there’s plenty of space. How can I resolve the persistent errors?

I@ve copied and pasted the latest log below:

[INFO] BackWPup 3.7.0; A project of Inpsyde GmbH
[INFO] WordPress 5.3.2 on https://www.curryoncooking.com/
[INFO] Log Level: Normal
[INFO] BackWPup job: Backup Website
[INFO] Logfile is: backwpup_log_b628ae_2020-03-13_16-35-16.html
[INFO] Backup file is: backwpup_2XXYFCU601_12eebd0b_2020-03-13_16-35-16.zip
[13-Mar-2020 16:35:16] 1. Try to backup database …
[13-Mar-2020 16:35:16] Connected to database nila0355_curryon on localhost
[13-Mar-2020 16:35:22] Added database dump “nila0355_curryon.sql” with 124.69 MB to backup file list
[13-Mar-2020 16:35:22] Database backup done!
[13-Mar-2020 16:35:23] 1. Trying to make a list of folders to back up …
[13-Mar-2020 16:35:24] Added “wp-config.php” to backup file list
[13-Mar-2020 16:35:24] 3415 folders to backup.
[13-Mar-2020 16:35:24] 1. Trying to create a WordPress export to XML file …
[13-Mar-2020 16:35:28] Check WP Export file …
[13-Mar-2020 16:35:29] WP Export file is a valid WXR file.
[13-Mar-2020 16:35:29] Added XML export “Curry_On_Cooking.wordpress.2020-03-13.xml” with 21.85 MB to backup file list.
[13-Mar-2020 16:35:30] 1. Trying to generate a file with installed plugin names …
[13-Mar-2020 16:35:30] Added plugin list file “Curry-On-Cooking.pluginlist.2020-03-13.txt” with 5.81 KB to backup file list.
[13-Mar-2020 16:35:30] 1. Trying to generate a manifest file …
[13-Mar-2020 16:35:30] Added manifest.json file with 6.17 KB to backup file list.
[13-Mar-2020 16:35:30] 1. Trying to create backup archive …
[13-Mar-2020 16:35:30] Compressing files as ZipArchive. Please be patient, this may take a moment.
[13-Mar-2020 16:39:01] Backup archive created.
[13-Mar-2020 16:39:01] Archive size is 572.23 MB.
[13-Mar-2020 16:39:01] 26905 Files with 1.45 GB in Archive.
[13-Mar-2020 16:39:03] One backup file deleted
[13-Mar-2020 16:39:03] 1. Try to send backup file to Dropbox …
[13-Mar-2020 16:39:03] /home/nila0355/public_html/wp-content/plugins/backwpup/inc/class-destination-dropbox-api.php: Dropbox API: (400) Bad input parameter: Error in call to API function “users/get_current_account”: This app is currently disabled.
[13-Mar-2020 16:39:03] 2. Try to send backup file to Dropbox …
[13-Mar-2020 16:39:03] /home/nila0355/public_html/wp-content/plugins/backwpup/inc/class-destination-dropbox-api.php: Dropbox API: (400) Bad input parameter: Error in call to API function “users/get_current_account”: This app is currently disabled.
[13-Mar-2020 16:39:03] 3. Try to send backup file to Dropbox …
[13-Mar-2020 16:39:04] /home/nila0355/public_html/wp-content/plugins/backwpup/inc/class-destination-dropbox-api.php: Dropbox API: (400) Bad input parameter: Error in call to API function “users/get_current_account”: This app is currently disabled.
[13-Mar-2020 16:39:04] ERROR: Step aborted: too many attempts!
[13-Mar-2020 16:39:04] 1. Trying to check database …
[13-Mar-2020 16:39:05] Database check done!
[13-Mar-2020 16:39:05] One old log deleted
[13-Mar-2020 16:39:05] ERROR: Job has ended with errors in 229 seconds. You must resolve the errors for correct execution.