Tracking page link doesn’t work

I use DHL UK for all uk shipments. So when i enter the shipment number it opens DHL tracking page.
Apart from the first one , none of the shipment links work. Every one of them opens up a page at the create
a new shipment page.
Is this because i need to change it to DHL express rather than DHL UK.
Which then creates a new problem, as when i am in Orders Tracking, it doesnt let me change the courier to a new
default carrier.
Any ideas why this is happening.
I have tried eliminating other plugins that may cause a conflict and also theme issues but no success.