PHP Syntax Update Fix

### Solution:
You need to modify the file `/wp-content/plugins/woocommerce-pdf-invoice-1/lib/barcodes/BarcodeGenerator.php` to replace the curly braces `{}` with square brackets `[]`.

#### Example Fix:
Locate line 292 (and potentially other lines) in the `BarcodeGenerator.php` file. It might look something like this:

$char = $data{$i}; // Old, outdated syntax

Change it to:

$char = $data[$i]; // Updated, supported syntax

#### Steps to Update:
1. **Access the file**:
– Use an FTP client, cPanel File Manager, or SSH to navigate to the file:
`/home/storm/sites/hbguq-nimsite-uk/public/wp-content/plugins/woocommerce-pdf-invoice-1/lib/barcodes/BarcodeGenerator.php`.

2. **Edit the file**:
– Open the file in a text editor.
– Search for any instances of `{}` used for string or array offsets.
– Replace all instances of `{}` with `[]`.

3. **Save the changes** and test your site to ensure the error is resolved.

### Alternative Solution:
If you are not comfortable editing the plugin files, consider:
– **Updating the plugin**: If an updated version of the `woocommerce-pdf-invoice` plugin is available, it might already include a fix for this issue.
– **Rolling back PHP version**: If you recently upgraded to PHP 7.4 or later, consider temporarily downgrading to PHP 7.3 (though this is a temporary fix and not recommended for long-term security).

### Additional Note:
Make a backup of your site before making any changes, especially if you're editing core plugin files.