Docker build not working

[nfacha]

Status: Downloaded newer image for goofball222/pritunl:latest
 ---> 89403d22ac7b
Step 2/12 : ENV ORIG_API_SERVER app.pritunl.com
 ---> Running in fb4d4b9bda87
Removing intermediate container fb4d4b9bda87
 ---> 6e4fc947fd7f
Step 3/12 : ENV FAKE_API_SERVER pritunl-api.simonmicro.de
 ---> Running in 7bf643674954
Removing intermediate container 7bf643674954
 ---> 8c962637a7b0
Step 4/12 : ENV ORIG_AUTH_SERVER auth.pritunl.com
 ---> Running in 03384c6c7313
Removing intermediate container 03384c6c7313
 ---> c65475329a41
Step 5/12 : ENV FAKE_AUTH_SERVER pritunl-api.simonmicro.de\\/auth
 ---> Running in 52ddd6296519
Removing intermediate container 52ddd6296519
 ---> 631bf0a3a816
Step 6/12 : RUN ORIG_API_SERVER_ESCAPED=$(echo "$ORIG_API_SERVER" | sed -e 's/\./\\./g') &&     FAKE_API_SERVER_ESCAPED=$(echo "$FAKE_API_SERVER" | sed -e 's/\./\\./g') &&     ORIG_AUTH_SERVER_ESCAPED=$(echo "$ORIG_AUTH_SERVER" | sed -e 's/\./\\./g') &&     FAKE_AUTH_SERVER_ESCAPED=$(echo "$FAKE_AUTH_SERVER" | sed -e 's/\./\\./g') &&     echo 'Rewriting pritunl api endpoint: libs' &&     find /usr/lib/python3.9 -type f -print0 | xargs -0 sed -i "s/$ORIG_API_SERVER_ESCAPED/$FAKE_API_SERVER_ESCAPED/g" &&     echo 'Rewriting pritunl api endpoint: www' &&     find /usr/share/pritunl/www/ -type f -print0 | xargs -0 sed -i "s/$ORIG_API_SERVER_ESCAPED/$FAKE_API_SERVER_ESCAPED/g" &&     echo 'Rewriting pritunl auth (SSO) endpoint: libs+www' &&     find /usr/lib/python3.9 -type f -print0 | xargs -0 sed -i "s/$ORIG_AUTH_SERVER_ESCAPED/$FAKE_AUTH_SERVER_ESCAPED/g" &&     find /usr/share/pritunl/www/ -type f -print0 | xargs -0 sed -i "s/$ORIG_AUTH_SERVER_ESCAPED/$FAKE_AUTH_SERVER_ESCAPED/g" &&     echo 'Done...'
 ---> Running in 1127eaa8c6b6
Rewriting pritunl api endpoint: libs
find: /usr/lib/python3.9: No such file or directory
sed: -i requires an argument
The command '/bin/sh -c ORIG_API_SERVER_ESCAPED=$(echo "$ORIG_API_SERVER" | sed -e 's/\./\\./g') &&     FAKE_API_SERVER_ESCAPED=$(echo "$FAKE_API_SERVER" | sed -e 's/\./\\./g') &&     ORIG_AUTH_SERVER_ESCAPED=$(echo "$ORIG_AUTH_SERVER" | sed -e 's/\./\\./g') &&     FAKE_AUTH_SERVER_ESCAPED=$(echo "$FAKE_AUTH_SERVER" | sed -e 's/\./\\./g') &&     echo 'Rewriting pritunl api endpoint: libs' &&     find /usr/lib/python3.9 -type f -print0 | xargs -0 sed -i "s/$ORIG_API_SERVER_ESCAPED/$FAKE_API_SERVER_ESCAPED/g" &&     echo 'Rewriting pritunl api endpoint: www' &&     find /usr/share/pritunl/www/ -type f -print0 | xargs -0 sed -i "s/$ORIG_API_SERVER_ESCAPED/$FAKE_API_SERVER_ESCAPED/g" &&     echo 'Rewriting pritunl auth (SSO) endpoint: libs+www' &&     find /usr/lib/python3.9 -type f -print0 | xargs -0 sed -i "s/$ORIG_AUTH_SERVER_ESCAPED/$FAKE_AUTH_SERVER_ESCAPED/g" &&     find /usr/share/pritunl/www/ -type f -print0 | xargs -0 sed -i "s/$ORIG_AUTH_SERVER_ESCAPED/$FAKE_AUTH_SERVER_ESCAPED/g" &&     echo 'Done...'' returned a non-zero code: 123
ERROR: Service 'pritunl' failed to build : Build failed