mine got slam, it fly nice

Another thought here is that the motors your using are pretty heavy at 18g. Even without the GoPo your copter is over 330g with the attached LiPo! BetaFPV and iFlight make motors that should work well for your copter but weight half as much.

IFlight https://shop.iflight-rc.com/index.php?route=product/product&path=20_26_149&product_id=895

Betafpv https://betafpv.com/collections/brushless-motors/products/1204-5000kv-brushless-motors

Ask yourself this question: How many Ducted commercial aircraft to you see flying around in Real-Life? Other then the high-bypass-jet engines being used, there are no other successful "Aviation" applications. For sure there have been lots of attempts but all have failed as the concept does really work / scale well in the real world. This in and of itself should tell you something!

IMO this only proves what I've been saying for a long time: "Ducts offer very little in the way of real performance gains, thus making their use with Quadcopters pretty pointless." (Its all just marketing hype) The larger the Duct, the greater the efficiency losses from the additional mass / drag. Its like adding a spoiler to a ricer-car. All you get is the go-fast appearance and not much in the way of real performance.

Biggest issue with Ducts is the additional mass from the Duct-Walls. Too thick of a wall and the copter being too heavy, flies like crap. On the other hand, thin walls while saving weight, allows the Ducts to harmonically / compressively oscillate as each propeller moves past. This can create a situation when the propeller could impact the wall at a very high speed. (Unplanned Rapid Disassembly) With larger duct sizes the Aerodynamic lift generated for the Duct-Lip only works while the Duct is in level flight. In other words as the copter Pitches / Rolls away from level flight, only the leading-edge of the Duct is creating additional lift. This has the unfortunate effect where the Ducts attempt to re-level the copter. In response the copters Flight Controller will counter this lift in an attempt to maintain the copters current orientation. Effectively any efficiency gains made by the Ducts are lost as the flight controller will burn through you battery to maintain orientation.

Lets get back to the "why" of it all.

The whole reason Ducts are used is to make a Quadcopter "safer" in confined environments, particularly indoors. With that in mind, its better to use Prop-Guards (no Duct lip) that fits snuggly (within 1-2 mm) around the propellers diameter. Ideally the Guards wall should only be 2-3 mm taller than the propeller to account for high RPM prop-flex. (Stiffer propellers are better for ducts / guards FYI)

Guards have the following advantages...

-Simpler design.
-Less mass.
-Less drag.
-Less noise.
-Not affected by the copters orientation.
-Less likely to break in a crash.
-Nice reduction in prop tip Vortices with efficiency gains of 3-5% to be expected. Which is usually just enough to offset the additional weight of the guards.
-Much easier to 3D-Print and repair.