EAP authentication failed <- OpenWrt 19.07.2 and Eduroam

System: OpenWrt 19.07.2 on a Raspberry Pi 3 (B+)

Im trying to connect with my Raspberry Pi to the Eduroam network with the following Identity and settings:

Identity: InstitutionID@myInstitution.de

wpa_suppicant.conf

network={
	scan_ssid=1
	ssid="eduroam"
	key_mgmt=WPA-EAP
	ca_cert="/etc/luci-uploads/T-TeleSec GlobalRoot Class 2.crt"
	identity="***@***.de"
	password="***"
	phase2="auth=MSCHAPV2"
	eap=PEAP
	proto=RSN
	beacon_int=100
}

General instructions how to set it up, can be found here (including link to certificate):

https://www.hrz.tu-darmstadt.de/netz/netzzugang_internet/netz_datennetz_internet_wlan_1/netz_wlan_anleitungen_1/netz_wlan_mobile_endgeraete_1/index~1.en.jsp

Somehow the connection can not be established (System Log):

Sat Apr  4 15:46:56 2020 daemon.notice netifd: Interface 'eduroam' is enabled
Sat Apr  4 15:47:23 2020 daemon.notice wpa_supplicant[5193]: wlan1: SME: Trying to authenticate with d4:68:4d:a5:e5:58 (SSID='eduroam' freq=2437 MHz)
Sat Apr  4 15:47:23 2020 kern.info kernel: [ 1540.773275] wlan1: authenticate with d4:68:4d:a5:e5:58
Sat Apr  4 15:47:23 2020 daemon.notice wpa_supplicant[5193]: wlan1: Trying to associate with d4:68:4d:a5:e5:58 (SSID='eduroam' freq=2437 MHz)
Sat Apr  4 15:47:23 2020 kern.info kernel: [ 1540.812542] wlan1: send auth to d4:68:4d:a5:e5:58 (try 1/3)
Sat Apr  4 15:47:23 2020 kern.info kernel: [ 1540.821285] wlan1: authenticated
Sat Apr  4 15:47:23 2020 kern.info kernel: [ 1540.827832] wlan1: associate with d4:68:4d:a5:e5:58 (try 1/3)
Sat Apr  4 15:47:23 2020 kern.info kernel: [ 1540.843525] wlan1: RX AssocResp from d4:68:4d:a5:e5:58 (capab=0x1431 status=0 aid=1)
Sat Apr  4 15:47:23 2020 daemon.notice netifd: Network device 'wlan1' link is up
Sat Apr  4 15:47:23 2020 daemon.notice netifd: Interface 'eduroam' has link connectivity
Sat Apr  4 15:47:23 2020 daemon.notice netifd: Interface 'eduroam' is setting up now
Sat Apr  4 15:47:23 2020 daemon.notice wpa_supplicant[5193]: wlan1: Associated with d4:68:4d:a5:e5:58
Sat Apr  4 15:47:23 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-EAP-STARTED EAP authentication started
Sat Apr  4 15:47:23 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-SUBNET-STATUS-UPDATE status=0
Sat Apr  4 15:47:23 2020 kern.info kernel: [ 1540.860988] wlan1: associated
Sat Apr  4 15:47:23 2020 daemon.notice netifd: eduroam (5303): udhcpc: started, v1.30.1
Sat Apr  4 15:47:23 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-EAP-PROPOSED-METHOD vendor=0 method=25
Sat Apr  4 15:47:23 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-EAP-METHOD EAP vendor 0 method 25 (PEAP) selected
Sat Apr  4 15:47:23 2020 daemon.notice netifd: eduroam (5303): udhcpc: sending discover
Sat Apr  4 15:47:23 2020 kern.debug kernel: [ 1540.982534] wlan1: Limiting TX power to 20 (20 - 0) dBm as advertised by d4:68:4d:a5:e5:58
Sat Apr  4 15:47:26 2020 daemon.notice netifd: eduroam (5303): udhcpc: sending discover
Sat Apr  4 15:47:29 2020 daemon.notice netifd: eduroam (5303): udhcpc: sending discover
Sat Apr  4 15:47:58 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-EAP-STARTED EAP authentication started
Sat Apr  4 15:47:58 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-EAP-PROPOSED-METHOD vendor=0 method=25
Sat Apr  4 15:47:58 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-EAP-METHOD EAP vendor 0 method 25 (PEAP) selected
Sat Apr  4 15:47:58 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-BEACON-LOSS
Sat Apr  4 15:48:00 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-EAP-FAILURE EAP authentication failed
Sat Apr  4 15:48:02 2020 daemon.notice wpa_supplicant[5193]: wlan1: Authentication with d4:68:4d:a5:e5:58 timed out.
Sat Apr  4 15:48:02 2020 kern.info kernel: [ 1580.014845] wlan1: deauthenticating from d4:68:4d:a5:e5:58 by local choice (Reason: 3=DEAUTH_LEAVING)
Sat Apr  4 15:48:02 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-DISCONNECTED bssid=d4:68:4d:a5:e5:58 reason=3 locally_generated=1
Sat Apr  4 15:48:02 2020 daemon.notice netifd: Network device 'wlan1' link is down
Sat Apr  4 15:48:02 2020 daemon.notice wpa_supplicant[5193]: wlan1: CTRL-EVENT-SSID-TEMP-DISABLED id=0 ssid="eduroam" auth_failures=1 duration=10 reason=AUTH_FAILED
Sat Apr  4 15:48:02 2020 daemon.notice netifd: Interface 'eduroam' has link connectivity loss
Sat Apr  4 15:48:02 2020 daemon.notice netifd: eduroam (5303): udhcpc: received SIGTERM
Sat Apr  4 15:48:02 2020 daemon.notice netifd: Interface 'eduroam' is now down
Sat Apr  4 15:48:02 2020 daemon.notice netifd: Interface 'eduroam' is disabled
Sat Apr  4 15:48:02 2020 daemon.notice netifd: Interface 'eduroam' is enabled

I already changed password, this should not be the problem. On my Android device, the connection is working fine with the same Access Point.