How to set new account creating optional in PayPal Express Checkout?

Is it possible to define creating a new PayPal account in PayPal Express Checkout as not required?

I'm try this my code and getting two different results - once new paypal account as optional and the other time as an essential.

METHOD => SetExpressCheckout
MAXAMT => 4.50
RETURNURL => https://...
CANCELURL => https://...
REQCONFIRMSHIPPING => 0
SOLUTIONTYPE => SOLE
NOSHIPPING => 0
LOCALECODE => EN
LANDINGPAGE => Billing
HDRIMG => http://.../logo.jpg
PAYFLOWCOLOR => 
CHANNELTYPE => Merchant
ALLOWNOTE => 0
PAYMENTREQUEST_0_SHIPTONAME => Stephan K Schwartz
PAYMENTREQUEST_0_SHIPTOSTREET => Heiligengeistbrücke 76
PAYMENTREQUEST_0_SHIPTOSTREET2 => Freistaat Bayern
PAYMENTREQUEST_0_SHIPTOCITY => Windsbach
PAYMENTREQUEST_0_SHIPTOSTATE => 
PAYMENTREQUEST_0_SHIPTOZIP => 91575
PAYMENTREQUEST_0_SHIPTOCOUNTRYCODE => DE
ADDROVERRIDE => 1
PAYMENTREQUEST_0_SHIPPINGAMT => 
PAYMENTREQUEST_0_CURRENCYCODE => EUR
PAYMENTREQUEST_0_PAYMENTACTION => Sale
L_PAYMENTREQUEST_0_DESC0 => 
L_PAYMENTREQUEST_0_NAME0 => Product name
L_PAYMENTREQUEST_0_NUMBER0 => 4260568520853
L_PAYMENTREQUEST_0_AMT0 => 2.50
L_PAYMENTREQUEST_0_QTY0 => 1
L_PAYMENTREQUEST_0_ITEMURL0 => https://....
L_PAYMENTREQUEST_0_NUMBER1 => tax
L_PAYMENTREQUEST_0_NAME1 => VAT 20%
L_PAYMENTREQUEST_0_AMT1 => 0.50
L_PAYMENTREQUEST_0_QTY1 => 1
PAYMENTREQUEST_0_ITEMAMT => 3.00
PAYMENTREQUEST_0_AMT => 3.00

Guest checkout is turned on, of course, in both cases. Version 109.0.

Solution

Ok after a few hours of trying I found out it's question about amount of order.

If a customer is paying small order under about 200 USD or 500 EUR (I couldn't find exact limits), the customer will be promped to get registered. (right side of the picture in question)

But if a customer is paying more than the above estimated amount, the registration is not required. (left side of picture in question)

Makes this sense or am I wrong?