Hello, ideally it should not get loose within such a short span. But there could be various reason which can cause that so once the lockdown is over visit the dentist and get it re cemented if it comes out. Or if the problem is with the crown cutting and the overall preparation of the bridge than a fresh impression need to be taken and to be sent to lab to get it re fabricated.
Next Steps
Till lock down avoid chewing hard from that side avoid sticking food too
Health Tips
Visit the dentist once lockdown is over