Hello,
Do you reproduce the issue if you enable your browser console and activate the feature to simulate a smartphone ?
Regarding your issue description, it looks like there is something the Stripe JavaScript which do not perform the initialisation.
The text "STRIPE_PLEASE_WAIT" is replaced by the Stripe content via the JS provided by Stripe itself.
So if the content is not replace, it generally related to wrong credentials, a SSL issue or an error raised in Stripe.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.