The problem you are having is that you are using
Reserved words in the table definition, so when they are being called in a statement they will need to be escaped.
Most IDEs for a language will highlight reserved/special/key- words and my general rule is to use different names when the colors change. This can be evidenced even in the CodeProject editor
insert into schedule(group,time,lecturer)values(...
Different DB Servers use different characters to escape reserved words; I believe MariaDB uses a back-tick to escape these, so your query would look like this
insert into schedule(`group`,`time`,lecturer)values(...
Here is the list of the words that MariaDB considers special:
Reserved Words - MariaDB Knowledge Base[
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