No interval is set for collector

[multiflexi]

I am getting this errors when no refresh interval is set for collector:

collectors_1  | [2023-03-06 13:36:38 +0100] [10] [DEBUG] [None] COLLECTOR rss/1e60d424-66f1-40e7-9e13-bc60fa7d0f1e: RSS returned feed with 13 entries
collectors_1  | [2023-03-06 13:36:38 +0100] [10] [DEBUG] [None] COLLECTOR rss/1e60d424-66f1-40e7-9e13-bc60fa7d0f1e: RSS collection exceptionally failed
collectors_1  | [2023-03-06 13:36:38 +0100] [10] [INFO] [None] OSINTSource ID: 1e60d424-66f1-40e7-9e13-bc60fa7d0f1e
collectors_1  | [2023-03-06 13:36:38 +0100] [10] [INFO] [None] OSINTSource name: Mikrotik
collectors_1  | [2023-03-06 13:36:38 +0100] [10] [INFO] [None] ERROR: string index out of range
collectors_1  | [2023-03-06 13:36:38 +0100] [10] [DEBUG] [None] Traceback (most recent call last):
collectors_1  |   File "/app/collectors/rss_collector.py", line 95, in collect
collectors_1  |     limit = BaseCollector.history(interval)
collectors_1  |   File "/app/collectors/base_collector.py", line 129, in history
collectors_1  |     if interval[0].isdigit() and ':' in interval:
collectors_1  | IndexError: string index out of range
collectors_1  | 
collectors_1  | [2023-03-06 13:36:38 +0100] [10] [DEBUG] [None] RSS_COLLECTOR collection finished.

Maybe there should be some default value or the refresh interval should be mandatory in order to avoid this issue. The source does not show up in Assess and the reason is not clear unless one tries to debug it.