Without achieving proficiency of multiplication facts, a student's difficulty may be compounded when they begin studying division, fractions, and solving problems with multi-digit numbers. That difficulty will likely come in the form of spending a considerable amount of time with basic calculations and not having much time for understanding new concepts.
Math Fact Fluency creates students who are confident in their abilities. Before learning multiplication facts, it is important for students to understand multiplication as "repeated addition". During my 20 years in the classroom, I always wanted my students to achieve the goal of "instant recall" (the ability to retrieve the answer instantly or within 3 seconds. This will vary based on a student's processing ability, but I have been witness to many students achieving this goal.
These days there are a variety of ways for students to practice leaning their multiplication facts without using flashcards and rote learning (writing a particular fact/facts repeatedly). Here are a few suggestions for helping your child improve:
1. Create arrays using manipulatives (e.g. Unifix Cubes, Counter Disks)
2. Play Multiplication War
3. Use Multiplication Coloring Worksheets
4. Playing online multiplication games (e.g. https://www.multiplication.com/games)
You can also get get creative and come up with your own multiplication game! Good luck!