Your status depends on when your residence card has expired. If the permit expired before 14/03/2020 and you did not manage to apply on the last day of legal stay at the latest, your stay in Poland cannot be considered legal.
If the validity of your permit expires after the 13/03/2020, i.e. after the state of the epidemic threat was announced, you are still staying in Poland legally. According to the regulations introduced on the 31/03/2020, the validity of your permit is automatically extended until the end of the 30th day following the date of cancellation of the epidemic state/epidemic emergency (the one that was in force last). You can apply by post only. If you do not have this option, the so-called anti-crisis shield legislation provides the extension of the deadlines for submitting applications for residence permits, if this deadline would fall during a period of epidemic emergency/epidemic status. As before, these applications may be sent to Governors' offices up to the 30th day following the date of cancellation of the last state (epidemic emergency/epidemic status). Your stay in Poland during this period will be considered legal, provided that you apply for the legalization of your stay in this extended period.