Haproxy ACL for query-string "Authorization"

I am trying to create ACL in Haproxy to query Authorization from request header and route to backend based on AccessID. I have used map file which are populated with AccessID and backend server. I am sure that my ACL is not working and hence I am getting 503 for incoming requests. Any help is appreciated!

Config File:

frontend  main
        bind *:80
        capture request header Authorization len 50
        acl GET_calls method GET HEAD OPTIONS
        acl PUT_calls method PUT

       use_backend %[req.hdr(Authorization),map_sub(/etc/haproxy/PUT_Header.map)] if PUT_calls

Map File:

# AccessID	backend server
JMYQ		get_s1
P2BH		get_s1
WEA1		get_s2

I have captured the request header in log and I see AccessID.

Apr  8 10:10:29 localhost haproxy[79517]: 0.11.4.1:929 [08/Apr/2022:10:10:29.232] main main/<NOSRV> -1/-1/-1/-1/0 503 212 - - SC-- 0/0/0/0/0 0/0 {Credential=WEA1} "PUT /common/Demo2.file HTTP/1.1"

I was able to get ACL working for individual query.

acl url_paramf req.hdr(Authorization) -m sub WEA1

But, map is not working as expected. ACL for Map

use_backend %[req.hdr(Authorization),map_sub(/etc/haproxy/PUT_Header.map)] if PUT_calls

I was able to achieve it by doing like this:

	acl headerlist hdr_sub(Authorization) -f /etc/haproxy/File
	use_backend get_sg1 if headerlist

        acl headerlist2 hdr_sub(Authorization) -f /etc/haproxy/File2
        use_backend get_sg2 if headerlist2

File

# AccessID
JMYQ		
P2BH		

File2

# AccessID
WEA1