The new glasses are not suitable, and often eyeglasses online cheap require adaptation. Some people can adapt to them in a while. Some people may need a longer time if their data changes significantly, they are older, or they are very sensitive.
Since you are asked to adapt, then adapt. Oftentimes, wearing it for a while will make everything fine. If the cheapest eyeglasses are suitable, they should improve and feel more comfortable day by day.
If there is no improvement day by day, one cannot force their eyes to adapt to glasses. We should wear our old glasses. Old glasses are your prescription history and can affect your prescription.
Verify whether the prescription and processing data for optometry meet the standards. If it is a processing error, then replacing the discountglasses lens and reprocessing will solve the problem. Many times, processing data is not a problem.
There is no problem with processing the data. Next, test the data of old and new glasses, record them one by one, and compare the changes between the old and new glasses.
Based on your question, take into account factors such as the wearing time, age, occupation, and intended use of the old glasses. Based on experience, guess the most likely reason or reasons and give you a trial to verify.
Processing is not a problem, but it is necessary to compare the curvature, forward tilt angle, and eye distance of the new and old glasses to see if there are significant differences. Observe whether the frame of the old glasses is severely deformed. Keeping the frame of new glasses as close as possible to the old glasses within a reasonable range often solves the problem.