Ash here from the Shopify team. Thank you for posting your question in the Shopify Community forums!
Amazon Pay is available to merchants located in specific countries and selling in USD, GBP, JPY, and EUR. The full list of supported countries is available in our Help Center. If you decide to deactivate Amazon Pay, provided that you're still selling in a supported currency and operating out of a supported country, you should be able to re-activate Amazon Pay in the future by following the steps to activate Amazon Pay on your account.
May I ask why you're considering deactivating this payment method temporarily? Do you need any assistance finding an alternative payment provider?
Thanks for swift reply. We have noticed over time that a small number of fulfilled orders are not being remitted by Amazon Pay. I'm not sure why some are paid and others remain outstanding so until I get this resolved I planned to temporarily deactivate this payment method.
Remembering how hard this payment method was to activate I was hoping that I was able to simplify switch off and reactivate using this button once the issue has been resolved.