How do I install on my Huawei p9 twrp [error]?

In itself, the installation should not be a problem. Have already installed multiple TWRP on a variety of devices but the Huawei p9 what I have here is really a mystery to me.

Unfortunately, I have to tell the whole story, maybe one of you still has an IDEA

Everything started about 1.5 years ago with the purchase of the device. The first time it was used quite normal [without root and twrp]. After half a year, there were some reasons why I needed root at that time still under Android 6.0, then simply root with the program "SRK Tool Huawei" was installed (the exact version is not known to me). It was not a problem at the time. So first bootloader Unlock then TWRP and then finally rooten.

But then when about a 3/4 year ago, the Android 7 update came I installed it quite normal on the phone (How to stop it as normal Android Stock User so)

That was not a big problem as far as I know was to update the phone from the system / update back set. After that, there was no root left (I did not check TWRP). The phone was then used for a 1/4 year normal until finally root was needed again. At that time (again with the SRK Tool Huawei) now it starts to the phone did not rooten anymore, TWRP was not findable so I tried a new installation of TWRP (Bootloader still unlocked). At that time there was not much time for it, so eventually I stopped searching where the mistake was.

A few weeks ago, it grabbed me again. I thought maybe it would be useful if I reset the operating system

Attempt: Reset via Huawei suite (there's an error message saying the program does not support the phone)
Try: About the eRecovery reset (worked) probelm afterwards it was on the Fresh OS no keyboard, Kamaera app. Ansich no problem simply connected to an adapter a desktop keyboard and everything set up. (Camera works tested via Whatsapp) Next and current problem is bluetooth can't start neither via external app nor on the settings. Flashlights feature of system bar also does not work. (Function given via eg Whatsapp or External Apps)

Resetting again as under point 2 was unsuccessful.

And now I try again But still no success. Days long google search also revealed no education.

Now my real question: How do I get it out once the normal system functions such as bluetooth and flashlight work again?

And how do I get it out If the TWRP works again and I can root the phone?

My approach was to first get TWRP under control and then just work with a Custome Rom.

But as you know, TWRP does not let me install my phone

Installation was tried over many different programs.

Here with bat file about fastboot

https://forum.xda-developers.com/...9-t3367800

Before now stupid comments come from because of why you rootet about why you need to come root.

I NEED all the official for testing purposes.

Already tried, maybe reading the TEXT

I do not know what you have tried everything because there are only different programs. Is there ne error message etc?

Short a question, is still an original os on the device?

Then you could try the phone again in the "Green State" mode to bring and experiment again from the beginning.
There's if necessary a manual, otherwise vllt try to transfer a manual from another phone.

Yes, it is still the original OS

It is problem I come with every attempt to start twrp in the eRecovery

Unfortunately, it is only about the fastboot command, the tools will all do the same and execute the. https://dl.twrp.me/eva/

You could try to rooten and then flashing over the twrp app

Can't be that original OS, if you already have another version installed.

YeWz")(,.)',).