Hi,
So I don't see any errors there which could be related to PayPal or Stripe not working. Maybe you would get more information for PayPal if you activate its "debug" setting. Could you try that ?
I can see however that the PayPal checkout plugin still uses the PayPal sandbox. As you're on a live website, I find this strange.
You said that the "client id" and "client secret" are correct. Does that mean that you were already using them on your website before ?
If so, I suppose that they are for your PayPal live account. In that case, they can't work with the PayPal sandbox.
If you activate the "sandbox" setting of the plugin, then you have to use the client id and the client secret of a sandbox account.
So please check the status of the "sandbox" setting of your PayPal checkout payment method.
Regarding Stripe I'm not sure. You said that you were "instructed to upgrade to the latest PayPal Checkout plugin". However, I can see that you're using HikaShop 5.0.4, from 2 months ago. The PayPal Checkout plugin being included in HikaShop, I'm not sure what this means. Does it mean that you were using another PayPal payment plugin and you switched to PayPal Checkout ? In that case, that means that nothing changed for Stripe and thus I don't see why it suddenly wouldn't work. Or does it mean that you updated your HikaShop 2 months ago ? But then you should already have the problem with Stripe for 2 months no ? Also, if you updated HikaShop, which version did you had before ? Maybe you have an old version of the Stripe plugin and you need to update it too ?