Uri not working

this is my configuration for the application. I am not getting expected output from the url - https://nexus-api-int.dev.se.com/INT/mapping. instead i get message forbidden.
but if i directly hit the backend server - https://q9497fp4ri-vpce-00fceacfc1d8fb2a2.execute-api.eu-west-1.amazonaws.com/INT/mapping i get correct output.
connection to backend is fine,as i see its UP in haproxy.

acl host_nexus-api-int_dev hdr_end(host) -i nexus-api-int.dev.se.com
acl uri_nexus-api-int-dev path_beg /INT/mapping

use_backend nexus-api-int_dev if uri_nexus-api-int-dev host_nexus-api-int_dev proto_HTTPS
http-request redirect scheme https if proto_HTTP host_nexus-api-int_dev

backend nexus-api-int_dev
# modsecurity blocking mode
#filter modsecurity modsec_blocking rules-file /etc/hapee-“$HAPEE_VERSION”/modsec-global/cfg_blocking.conf
# modsecurity logging mode
filter modsecurity modsec_logging rules-file /etc/hapee-“$HAPEE_VERSION”/modsec-global/cfg_logging.conf
balance leastconn
http-request set-path %[path,regsub(^/INT/mapping,/INT/mapping)] if { path_beg /INT/mapping }
option httpclose
option forwardfor
http-send-name-header host
server-template node 3 q9497fp4ri-vpce-00fceacfc1d8fb2a2.execute-api.eu-west-1.amazonaws.com:443 ssl verify none check resolvers dnsSE-refresh resolve-prefer ipv4

have you checked “who” sends forbidden? haproxy or your backend server. can you see the request on the backend server?

no, no requests at backend server