Problem with shipping cost calculation

We are responsible for maintaining our customer’s online shop. The customer has now informed us several times that the shipping costs are being calculated incorrectly. For example, €495 is being charged instead of €4.95. However, our developer has checked all the settings in Woo Commerce and they all appear to be correct. Furthermore, it does not happen every time. Customers also have the problem that when they try to adjust the shipping costs themselves, the changes are not applied. Our developer thinks this could possibly be related to the Germanized plugin. Do you have any suggestions for a solution? Best regards

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