Display of patient record hangs

[djhshih]

I've setup matchminer-api on localhost:5000.
I loaded the test data (TCGA) into the monogdb based on https://matchminer.gitbook.io/matchminer/matchminer-api/development-setup

I then gulp serve this matchminer-ui website, which is configured to access the API at the correct URI of localhost:5000.

Through the web site served at localhost:8001, I can find a particular patient by MRN, e.g. "a4777":

mm-api  | [INFO] 172.21.0.1 - - [21/Jan/2023 13:32:31] "GET /api/filter?cacheBuster=1674307951151&where=%7B%22TEAM_ID%22:%225a8ede8f4e0cce002dd5913c%22,%22temporary%22:false,%22status%22:%7B%22$in%22:%5B0,1%5D%7D%7D HTTP/1.1" 200 -

But when I clicked the action icon to go to patient record, the server logs

mm-api  | [INFO] 172.21.0.1 - - [21/Jan/2023 13:37:43] "GET /api/utility/count_match?cacheBuster=1674308263499 HTTP/1.1" 200 -

while the web page just hangs, showing only "Loading patient details..." for several minutes with no progress.

Is there a particular schema that matchminer-ui or matchminer-api expects?
Does the provided test data follow this schema? If so, why does the web page fail to retrieve the fake/test patient record?