It seems that in 294537f084ad617ed8b5df30d25f8c0df6fa3e98 the call to AmazonFlexPay.multi_use_pipeline was updated to use the method signature provided in amazon_flex_pay 0.10.0. Gemfile.lock file still lists amazon_flex_pay 0.9.13, which is incompatible, so it should be updated.
It seems that in 294537f084ad617ed8b5df30d25f8c0df6fa3e98 the call to AmazonFlexPay.multi_use_pipeline was updated to use the method signature provided in amazon_flex_pay 0.10.0. Gemfile.lock file still lists amazon_flex_pay 0.9.13, which is incompatible, so it should be updated.