版本冲突

[LeftH0ok]

Using version ^5.1 for riverslei/payment
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Problem 1
- Installation request for riverslei/payment ^5.1 -> satisfiable by riverslei/payment[v5.1.0].
- riverslei/payment v5.1.0 requires guzzlehttp/guzzle ~6.0 -> satisfiable by guzzlehttp/guzzle[6.0.0, 6.0.1, 6.0.2, 6.1.0, 6.1.1, 6.2.0, 6.2.1, 6.2.2, 6.2.3, 6.3.0, 6.3.1, 6.3.2, 6.3.3, 6.4.0, 6.4.1, 6.5.0, 6.5.1, 6.5.2, 6.5.3, 6.5.4, 6.5.5, 6.5.x-dev] but these conflict with your requirements or minimum-stability.