Due to the feature to create an order from the backend quotation view it can cause an issue while simultaneously working on an order. It can incorrectly link the order to the quotation if you work on both in a specific order. To prevent this issue don't work simultaneously or if you never make use of the order creation feature in the quotation view or do not care about it not being linked you can implement the following fix.
Create a new module
1. Create a preference for Cart2Quote\Quotation\Observer\Quote\ConvertedToOrder.php
2. Extend the original class in preference
3. Overwrite Execute() to the following:
public function execute(EventObserver $observer)
// do nothing