paypal does not work checkout step 3 is giving bad request

[ngi]

Hi there,
great to have a forum to get some feedback about problems ..

I have a store which worked a time but at the moment I am not abl to get pypal working.
It's joomla 1.5.22 and virtuemart 1.5..
I chekced all paypal api settings several times..
Two peoblems accure:
I woud like to offer just paypal for chekcout.. it worked but since a week I always have the option to pay via credit card aswell.. The only Option for paying is set to paypal... ?!

The more worse problem is that if I test the payment process I get a bad request at the shop main page. I do not know how to handel it.. maybe some of you could help me....
I searched for solutions for many hours in several topis but it seems to be the fist time that this message appears..
please see attached picture..

thanks in advance..
nico

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