can't fill &Sign Protected PDF on IPad Acrobat

I created a password protected filable form which is enable printing, fill & sign and add comment. It's 128 bit AES encrypt and support acrobat7.0 and later. 

I found this form can't fill and sign in IOS acrobat pro(Ver 21.01.04), all the filed is blank. Can anyone help me what's is the problems? Thanks!