2 standard payment plugins - one not working

[melsonmarketing]

Hi!
I hope you're all doing fine.

I have a problem on the site https://www.foerst-class.de

We are using PayPal plus and two standard paymentplugins configured to

auf Rechnung (invoice) and
Vorkasse (cash in advance)

While Invoice is working fine, cash in advance won't work at all.

Do you have any ideas what could cause this?

Thanks for your hints and stay healthy!

+++EDIT+++
J! 3.9.16
VM 3.6.10
Php 7.3.5

Sorry I wasn't clear enough:

This happens when you hit the "Buy" Button.
The order can't be placed and an errormessage says, that no payment was choosen

[Jörgen]

I see very long update times in the cart long rotating hour glasses. But I can not see Your error, seems to work for me. Try with Protostar template.

Jörgen @ Kreativ Fotografi

[melsonmarketing]

Thank you for your answer Jörgen

Sorry I wasn't clear enough:

This happens when you hit the "Buy" Button.
The order can't be placed and an errormessage says, that no payment was choosen

[Jörgen]

I still thnk this is template dependant. Maybe Your admin tools is also interfering.

Jörgen @ Kreativ Fotografi

[melsonmarketing]

Yeah I'll try when there's less traffic.

In the meantime I also found out, that it might be caused by the PayPalPlus Plugin - already contacted the developer over there.

Thanks anyhow - I'll come back and report...

[Jörgen]

That is a very good guess. All payment methods get called and they are responsible to filter out their own data. This could interfere with other methods.

Jörgen @ Kreativ Fotografi