Problems with upper layers

[Lollodan]

HI, I tried to print the dog, but the printed object isn't good: I changed the nozzle, the filament (with Geeetech silky blak, code 700-001-1204), I placed the printer into a box in order to prevent cold air, the printer is well calibrated....everything without any result.
The objects I printed are shown in the pictures: only with the filament sent with the printer (the gray one) the structure is solid, why? Again, why the base isn't attached t the body of the stamp?
The belts are rightly tighten

[Lollodan]

Hi, last update: I cleaned the heat unit, controlled all settings, but the result is the same.....I suppose under-extrusion is the problem, I'm gonna try to update the FW, I hope it will help....Stay tune for more crushes....

[Lollodan]

Hi, as I said before, I tried to upgrade the firmware, but, surprise, the motherboard type isn't recognized by the pc, even if I'd already installed the proper driver....see the attached picture, where it's written, in Italian, "unknown motherboard" and it's impossible to upload the firmaware...I tried to change the Arduino settings (arduino 1.8.5) for the board Mega 2560 and Mega ADK, without success...

Can you please help me?

[William]

Hello, since you have replaced the nozzle, the extruder has been calibrated, the filament has been replaced, and the hot end has been cleaned. This still happens. So I want you to make a few suggestions:
1. Your consumables may be oxidized, resulting in poor extrusion. You can change to another consumable variety, of course this is not the first choice.
2. Is your firmware problematic, have you downloaded the correct port? You can download it from the link below. https://www.geeetech.com/download.html?download_id=40, download according to the mark of the picture (for Windows system and mac system)
3. You can make a mark on the consumable while extruding the consumable, and then extrude the 100mm consumable through the control screen to see if the 100mm consumable can be extruded correctly. If it is less than 100mm, it is a problem with the extruder.
4. If your first layer is not sticky, you can set the thickness of the first layer on the slicing software to increase it, and set the printing speed of the first layer to slow down as much as possible to make it stick to the hot bed. You can also level the hot bed manually or stick a layer of solid glue on the first layer.
5. To be on the safe side, you can see if the hot bed temperature is 60°C and the nozzle temperature is 215°C.
Best Wishes