Ultimate Membership Pro Stripe Payment Not Working

Hello,

I have applied the webhook (including all events) to my website (https://physiofromhome.com/?ihc_action=stripe).

However, whenever someone tries to sign up on the website, they are redirected to an empty page with the URL: https://physiofromhome.com/wp-content/plugins/indeed-membership-pro/public/stripe_checkout_v2_payment.php?sessionId=cs_live_ (and then my Publishable key etc).

Can anyone help please?