F5 BIG-IP APM with SAML on simplesamlphp

I have configured the F5 BIG-IP for SAML authentication. My IDP is simplesamlphp. I have configured SAML SP Provider and External IDP connector and connected it to Virtual Server. On simplesamlphp I added an application by importing xml metadata from BIG-IP. Communication works, authentication passes, but finally BIG-IP reports to me on Virtual Server:

Access was denied by the access policy. This may be due to a failure to meet access policy requirements.

In the apm log I have the information:

/ Common / SAML_ACCESS_POLICY: Common: ff7ec2b7: SAML Agent: / Common / SAML_ACCESS_POLICY_act_saml_auth_ag failed to parse assertion, error: Response is not encrypted

I cannot log in to F5 BIG-IP APM.