XA2 Ultra latest update to 50.1.A.5.59 as stopped SMART LOCK WORKING CORRECTLY

[Biggestted]

My device updated on the 30/03/18 and since then the SMART LOCK function as not been working correctly. After a restart the settings for the SMART LOCK function are blank, I have found a temporary solution in an older thread /t5/Xperia-XZ1-Compact/Smart-Lock-empty-after-update/m-p/1268741#M450 ,which indicates this is an ongoing issue with Andriod 8.0.

I do not understand though, that my device that came with 8.0 from the start as worked with SMART LOCK for over a month since I got it with no problem, but since it updated the other day to include the 1 March 2018 security patch level, SMART LOCK is now no longer working correctly. Also the above thread link as been going on since October 2017 with users experiencing the same problem since then.

As anyone else's XA2/XA2 Ultra recently updated and is having the same issue with the SMART LOCK function?

[Hellanwait]

Every time I restart my phone Smart Lock disapears....

Yes I know how  to disable the trusted agent and reboot again, back to settings to check to see if its there. Its getting really anoying, almost to the point I may start looking for a new phone. 

[Rumen2]

Hi I have a problem. When I try to go in Smart Lock I enter my password and screen is white. Maybe doesn't work correctly. And I searching for a solve the problem. Can anyone help.