Air Filter

I have a four year old 2.5 ton International Comfort Product A/C system that sucked my filter into the air handler’s fan.

I called my service technician and he told me I don’t have enough return air vents.

I live in a single story 1800 sq/ft home with a 350 sq/ft bonus room over my garage.

Can anybody provide me with other possible reasons.

wrong size filter, improperly installed filter, filter so dirty that it became blocked.

Microparticle performance rating might be too high, trapping smaller particles but not suited to a higher air flow. I would try a less restrictive filter.

Trying to second guess a tech that was on-site can be difficult without any other information. How many return air vents did the home have? Was the bonus room over the garage present when the original system was sized and installed? Or was it added after the fact? What geographic area are you located in?