Unable to connect to LDAPS

I installed LDAPS certificate on my domain controller, however, when I use LDP to make a connection on port 636, I get the error:

Error <0x51>: Fail to connect <g class="gr_ gr_29 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" data-gr-id="29" id="29">ldaps</g>

Any suggestions to resolve this issue.