hy Aldiya, i understand you frustration, but ocs-inventory is a community driven open source project where it can happen that schedule cannot always be met.
You can go into debug mode in ocs to find out the necessaray sql command to delete a computer older than xx days.
Than you can add a trigger or a stored procedure to mysql to delete the computer obects.
if you find the solution you can post it here.
Please be patient and please post a bug report in github. I think this forum is not as much noticed as github by the developers.
i wonder how many computers you have in your database to have to delete so often
a ocs-inventory user