[Exim] Combining expansion conditions

Hello,

I'm trying to nest multiple conditions.

It seems there is still a syntax error:

plain:
  driver = plaintext
  public_name = PLAIN
  server_condition ="${if or {\
                { and\
                        {\
                                {eq{$2}{ph10}\
                                {eq{$3}{secret}\
                        }\
                }\
                { and\
                        {\
                                {eq{$2}{ph20}\
                                {eq{$3}{secret2}\
                        }\
                }\
                }{1}{0}\
        }"

AUTH PLAIN AHBoMTAAc2VjcmV0

SMTP<< AUTH PLAIN AHBoMTAAc2VjcmV0
plain authenticator:
$1 =
$2 = ph10
$3 = secret
expansion failed: missing } at end of condition inside "and" group
SMTP>> 435 Unable to authenticate at present
435 Unable to authenticate at present
LOG: MAIN REJECT



Where does exim expect an additional bracket?

An extra bracket would mean unbalanced brackets?