failed to add service - already in use error

I compiled SFML library and my app on Raspbian with this tutorial https://github.com/oomek/sfml-pi. After this I moved shared objects and app to buildroot system for Raspberry Pi 4. I chosed DISPMANX version, my goal was to run app without X server.

When I try to run app, I have error failed to add service - already in use?. I know that there was many similar topics, I tried this solutions:

1. Comment dtoverlay=vc4-kms-v3d in config.txt -> this line didn't existed in my config.
2. Change gpu_mem to 128 -> any improvement

My config.txt:

# Please note that this is only a sample, we recommend you to change it to fit
# your needs.
# You should override this file using a post-build script.
# See http://buildroot.org/manual.html#rootfs-custom
# and http://elinux.org/RPiconfig for a description of config.txt syntax

# We always use the same names, the real used variant is selected by
# BR2_PACKAGE_RPI_FIRMWARE_{DEFAULT,X,CD} choice
start_file=start.elf
fixup_file=fixup.dat

kernel=zImage

# To use an external initramfs file
#initramfs rootfs.cpio.gz

# Disable overscan assuming the display supports displaying the full resolution
# If the text shown on the screen disappears off the edge, comment this out
disable_overscan=1

# How much memory in MB to assign to the GPU on Pi models having
# 256, 512 or 1024 MB total memory
gpu_mem_256=128
gpu_mem_512=128
gpu_mem_1024=128
gpu_mem_1024=192
gpu_mem=128

# fixes rpi (3B, 3B+, 3A+, 4B and Zero W) ttyAMA0 serial console
dtoverlay=miniuart-bt

On buildroot I set opengl from gst1-plugins-base with dispmanx, gles2, egl and wayland. I didn't set mesa-3d.

Any idea how can I make my app working? Should I add something to my config.txt?