Trouble with Civicron.php
You are not providing much background information. However, the following question/answer may be related:
Failed loading &quot;ioncube_loader_lin_7.2.so&quot; Cron Error after CiviCRM &amp; WordPress Upgrades

In short: There was a mismatch of php versions after an upgrade. Probably, a good starting point for you would be to check, if there have been any recent system upgrades.

In general, it would be helpful to state your civi version, the type and version of cms you are using, the command line you are trying to run plus any related messages and possibly any changes before the problem occured.