Hebrew Modal Verbs in Past tense
The use of Hebrew modal (helping) verbs in present tense is very straight-forward, but I'm confused with their past tense as in the following:

אֲנִי לֹא הָיָה מְסֻגָּל לָלֶכֶת בַּזְּמַן לִשְׂדֵה הַתְּעוּפָה. is this correct, or could I also say
אֲנִי לֹא יכולתי לָלֶכֶת בַּזְּמַן לִשְׂדֵה הַתְּעוּפָה.

תּוֹדָה רַבָּה

Question

Hebrew Modal Verbs in Past tense
The use of Hebrew modal (helping) verbs in present tense is very straight-forward, but I'm confused with their past tense as in the following:

אֲנִי לֹא הָיָה מְסֻגָּל לָלֶכֶת בַּזְּמַן לִשְׂדֵה הַתְּעוּפָה.  is this correct, or could I also say 
 אֲנִי לֹא יכולתי לָלֶכֶת בַּזְּמַן לִשְׂדֵה הַתְּעוּפָה.

תּוֹדָה רַבָּה

Answer

The first sentence is incorrect. The second is correct and could also be
אני לא יכולתי ללכת...