When I import my model into Blockbench I get an error "

TypeError: Cannot read properties of undefined (reading 'length')
at $5b (PLUGINS/(Plugin):cpm_plugin.js:2141:205)
at Function.B6b (PLUGINS/(Plugin):cpm_plugin.js:2158:53)
at Array.d (PLUGINS/(Plugin):cpm_plugin.js:19:47)
at Object.dispatchEvent (file:///C:/Users/beatr/AppData/Local/Programs/Blockbench/resources/app.asar/js/api.js:314:26)
at updateSelection (file:///C:/Users/beatr/AppData/Local/Programs/Blockbench/resources/app.asar/js/misc.js:211:13)
at g7b (PLUGINS/(Plugin):cpm_plugin.js:2183:98)
at G_b (PLUGINS/(Plugin):cpm_plugin.js:1924:1640)
at N_b (PLUGINS/(Plugin):cpm_plugin.js:1931:40)
at Function.A0b (PLUGINS/(Plugin):cpm_plugin.js:1958:66)
at d (PLUGINS/(Plugin):cpm_plugin.js:19:47)"

and the model doesn't load correctly. I can't do anything.