I have the same grippe.
I was talking in deep in the weed OSM signal group and apparently its a split between the address data not being present, and OrganicMap / CoMap being bugged.
The way to triage is asking nominatim, the geocoder from OSM. If it can resolve : its on the client side, if not, its a data problem.
I'm just parroting here. Happy to learn more.
This is THE only issue I have with those OSM client ( I don't care about traffic )
For good (server) search, one needs many layers (Photon, Pelias with OpenAdresses, Overpass, in-house pmtiles, etc.) using many DBs, each needing server ressources or expensive paid APIs.
It's obvioulsy expensive in terms of ops + dev, but also just to host.
It can't scale with only 0,0001 % of users donating to the app.
Fortunately, NLNet's there to fund work, but it's still nonethless only a tenth of what would be needed.
Plus map applications and general search engines don't talk to each other... I don't know why, but it is so. Maybe because all the well-known search engines are closed-source ?