What should I do if the pressure values fall too much with Bisoprolol?

Hello. In general, I have a low pressure which is 100/70 or 90 /48 detected in me too low pulse doctor prescribed me bisoprolol which can jeszcse more lower my pressure on the leaflet is also written that people with low pressure did not take the drug I contacted my doctor but he still tells me to try taking the drug and here my question is whether I should take it and what to do when my pressure drops too much? Thank you in advance for your reply