Fillable fields not working in iOS + purple highlight

Hello. I have created a document with fillable fields using Acrobat DC, and have applied a permissions password to this document.  It seems that since applying a password,  the document fields no longer function in iOS.  My guess is that the document was flattened when opened in the mobile applicaiton. I have conducted a test with the same document, unlocked, and the fields remain active.

Also, is there a way to turn off the purple highlight covering the fillable fields in iOS ?  The colour overwhelms the design of the document and it would be nice if it was offered as an optional feature.

Thank you.