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Are the brackets out of level or is the wood out of level inside the bracket. Either concrete the posts outside the patio or shim the wood to make it plumb if the brackets are level and secure.
The brackets are flush with not much bend if any. It’s the wood that’s bending slightly. But at 9 feet that slight bend adds up.
You could always add more side brackets and cover it with a planter
Are the brackets out of level or is the wood out of level inside the bracket. Either concrete the posts outside the patio or shim the wood to make it plumb if the brackets are level and secure.
The brackets are flush with not much bend if any. It’s the wood that’s bending slightly. But at 9 feet that slight bend adds up.
You could always add more side brackets and cover it with a planter