Here's the text of Rule 165a:
1. Failure to Appear. A case may be dismissed for want of prosecution on failure of any party seeking affirmative relief to appear for any hearing or trial of which the party had notice. Notice of the court's intention to dismiss and the date and place of the dismissal hearing shall be sent by the clerk to each attorney of record, and to each party not represented by an attorney and whose address is shown on the docket or in the papers on file, by posting same in the United States Postal Service. At the dismissal hearing, the court shall dismiss for want of prosecution unless there is good cause for the case to be maintained on the docket. If the court determines to maintain the case on the docket, it shall render a pretrial order assigning a trial date for the case and setting deadlines for the joining of new parties, all discovery, filing of all pleadings, the making of a response or supplemental responses to discovery and other pretrial matters. The case may be continued thereafter only for valid and compelling reasons specifically determined by court order. Notice of the signing of the order of dismissal shall be given as provided in Rule 306a. Failure to mail notices as required by this rule shall not affect any of the periods men*tioned in Rule 306a except as provided in that rule.
2. Non-Compliance With Time Standards. Any case not disposed of within time standards promulgated by the Supreme Court unders its Administrative Rules may be placed on a dismissal docket.
3. Reinstatement. A motion to reinstate shall set forth the grounds therefor and be verified by the movant or his attorney. It shall be filed with the clerk within 30 days after the order of dismissal is signed or within the period provided by Rule 306a. A copy of the motion to reinstate shall be served on each attorney of record and each party not represented by an attorney whose address is shown on the docket or in the papers on file. The clerk shall deliver a copy of the motion to the judge, who shall set a hearing on the motion as soon as practicable. The court shall notify all parties or their attorneys of record of the date, time and place of the hearing.
The court shall reinstate the case upon finding after a hearing that the failure of the party or his attorney was not intentional or the result of conscious indifference but was due to an accident or mistake or that the failure has been otherwise reasonably explained.
In the event for any reason a motion for reinstatement is not decided by signed written order within seventy-five days after the judgment is signed, or, within such other time as may be allowed by Rule 306a, the motion shall be deemed overruled by operation of law. If a motion to reinstate is timely filed by any party, the trial court, regardless of whether an appeal has been perfected, has plenary power to reinstate the case until 30 days after all such timely filed motions are overruled, either by a written and signed order or by operation of law, whichever occurs first.
4. Cumulative Remedies. This dismissal and reinstatement procedure shall be cumulative of the rules and laws governing any other procedures available to the parties in such cases. The same reinstatement procedure and timetable is applicable to all dismissals for want of prosecution including cases which are dismissed pursuant to the court's inherent power, whether or not a motion to dismiss has been filed.
It sounds like you either missed a court date or did not get this taken care of in a timely manner.