My Apple Pay has suddenly stopped working. on my iPhone 6s Plus.

My Apple Pay has suddenly stopped working. on my iPhone 6s Plus. Have tried everything that I’ve been advised to do. Rebooted phone, logged out & back in. Removed & reapplied the card, removed phone from case, updated latest software & held phone closer to machine & it still doesn’t work. It’s happening at various shops that I usually go to. Can anyone help with this.

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