Checking just the 10yd and 55yd poi is insufficient to diagnose a cant problem. Zero at the apex and then check your 10 yard and 55 yard windage.
If the three points (10yd, apex, 55yd) are in a perfect line, you have only a scope cant problem. You will need to rotate the scope in the mounts. If the three points are not in a line, you definitely have a gun cant problem (and you might still have a scope cant problem). First order of business when shooting multiple distances with significant rise and drop, is fix any scope cant problem. Scope cant cannot be fixed with a bubble level. Once you fix the scope cant, you can use a bubble level while shooting in the field to correct for any gun cant.