No shipping options were found

Hi,
I have tried to contact through your support page but received no response. There does not appear to be any other way to contact you, hence having to resort to WordPress forum.
I have installed your plugin in WordPress / Woocommerce, replacing a plugin I used to use called Oz Post for Woocommerce.
I am hoping to use your services in the future, but have a small issue with quantities.

It would appear that when I increase the quantity of a product or choose a large product, I get the message “No shipping options were found”. Smaller quantities work fine and show quotes.
I’ve tried to figure out what the threshold is, but it seems pretty random from product to product.
As this Website is a wholesale website, sizes and weights vary from envelope size to shipping container sizes and everything in between.
Is this a limitation of your platform that only relatively small packages are manageable or am I doing something wrong?
The previous Plugin I used “Oz Post” is sadly no longer working and it appears that the developer is not really interested in addressing the issues. However, when activated, it does allow any size or weight to be processed. This confirms that my shipping is set up correctly in WooCommerce. However when I remove ‘Oz Post’ and use ‘Easyship’, I get this problem.

Please can you advise as I would very much like to use your services. Also, how do your customer obtain support?

Thanks in advance.

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