It depends on who recorded the lien. If your company recorded the lien, you simply need to record a Notice of Release of Lien. If one of your subcontractors or suppliers recorded the lien, you will need to post a bond to release the lien.
If the job was not entered in March and it opened and ended in that month and we had not billed it at all till this week? Can we still Lien?
If the Project is still going the yes. If the Project began and ended with your work, then you have probably let the window expire to record a lien. Rule is 90-days from the date of last providing labor or materials, or completion of the project, whichever is last. You still have other claims against the owner though, so you are not left without remedies. You should speak with a construction attorney to see what uption you have if the amount is significant enough to want to recover the money.