Try manually resetting your plugins (no Dashboard access required). If that resolves the issue, reactivate each one individually until you find the cause.
If that does not resolve the issue, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel, navigate to /wp-content/themes/
and rename the directory of your currently active theme. This will force the default theme to activate and hopefully rule-out a theme-specific issue (theme functions can interfere like plugins).
If the above steps do not help resolve the issue, then try Manually upgrading. When all else fails, download a fresh copy of the WordPress (top right on this page) to your computer, and use that to copy up. Access your server via SFTP or FTP, or a file manager in your hosting account’s control panel (consult your hosting provider’s documentation for specifics on these), and delete then replace the wp-admin and wp-includes folders on your server (NOTE: do not delete the?wp-content?directory or your?wp-config.php?file). Read the?Manual Update directions first.
BACKUP: If you haven’t already done, always backup everything (including your database) before doing any actions, just in case something really goes wrong. You can never have enough backups! See https://www.ads-software.com/support/article/wordpress-backups/